List of articles (by subject) Structural Engineering

    • Open Access Article

      1 - Modeling of Accumulated Energy Ratio (AER) for Estimating LiqueFaction Potential Using Artificial Neural Network (ANN) and Gene Expression Programming (GEP) (using data from Tabriz)
      Armin Sahebkaram Alamdari Rouzbeh Dabiri Rasoul Jani Fariba Behrouz Sarand
      10.22094/jseg.2021.688673
      Presenting a model specific to the city of Tabriz to estimate the liquefaction potential due to the region's seismicity and the high groundwater level can be effective in dealing with and predicting solutions to deal with this phenomenon. In recent years, the accumulati More
      Presenting a model specific to the city of Tabriz to estimate the liquefaction potential due to the region's seismicity and the high groundwater level can be effective in dealing with and predicting solutions to deal with this phenomenon. In recent years, the accumulation energy ratio (AER) as a parameter for estimating the liquefaction potential in the energy-based method proposed by Kokusho (2013) has been considered by many researchers. In this research, using perceptron multilayer (MLP) and radial base function (RBF) methods in artificial neural network (ANN) and genetic expression programming (GEP), the accumulation energy ratio using seismic and geotechnical data is modeled for the city of Tabriz. These modeling’s performed by all three methods are well consistent with the outputs. Still, the modeling performed using the Perceptron Multilayer (MLP) method is very compatible with the outputs and can estimate the results with an acceptable percentage. The relationship presented by genetic expression programming (GEP), which is trained with local data, can also yield satisfactory results from estimating the rate of accumulated energy in the study area and provided an independent and accessible relationship trained. With data specific to the study area, there is another advantage. Manuscript profile
    • Open Access Article

      2 - A Numerical Study on the Seismic Performance of a RC-Bridge With Random Pier Scouring
      Ali Raoof Mehrpour Hosseini Mehran Seyedrazzaghi Nasser Shamskia
      10.22094/jseg.2023.1998635.1127
      A multi-hazard investigation approach is a vital requirement for a realistic risk assessment of infrastructures. The combined impact of scouring and earthquake can result in a distinctive effect on the performance of a given bridge. Scouring, being a hazard influenced b More
      A multi-hazard investigation approach is a vital requirement for a realistic risk assessment of infrastructures. The combined impact of scouring and earthquake can result in a distinctive effect on the performance of a given bridge. Scouring, being a hazard influenced by various factors, entails numerous uncertainties. Several prior investigations have explored the multi-hazard of scour-earthquake; however, the associated implementation has not accounted for the random scour depths around the foundations of differing bents. This study provides a probabilistic platform to investigate the effect of random scouring on the seismic performance of a multi-span RC bridge. In this regard, researchers employed Monte Carlo simulation to develop a probability hazard curve for scour. The Latin Hypercube technique was applied to randomly select depths, enabling the generation of non-uniform patterns for the depth of cavities formed in different foundations. Subsequently, the study involved conducting non-linear time history analyses on the finite element model. The uniform scouring patterns were also examined to compare the models. The scouring around foundations significantly affects the responses of bridge elements, as it influences the total base shear of the structure and the pounding forces between the superstructure elements. Manuscript profile
    • Open Access Article

      3 - Numerical Modelling of Dynamic Compaction in Dry Sandy Soils for Determination of Effective Print Spacing
      Ghodrat Jahangiri ali pak Ali Ghassemi
      Dynamic compaction (DC) is a widely used soil improvement method in dry and/or saturated soils. The design of DC treatment is usually carried out based on the past experiences and empirical relations. In order to clarify the ambiguities in DC processes, numerical modeli More
      Dynamic compaction (DC) is a widely used soil improvement method in dry and/or saturated soils. The design of DC treatment is usually carried out based on the past experiences and empirical relations. In order to clarify the ambiguities in DC processes, numerical modeling of DC in dry granular soils has been considered using a dynamic finite element code. Using the developed model, two design curves for determination of effective print spacing (distance between two neighboring drop points) in dynamic compaction of dry sandy soils are proposed. A case history of dynamic compaction project is analyzed and the obtained results show that the developed design curves have good capability for determination of print spacing Manuscript profile
    • Open Access Article

      4 - A Comparison of Seismic Safety of Steel MRF Designed According to Different Editions of Iranian Seismic Code
      kiarash Nasserasadi
      In this paper, efforts are made to compare the safety of steel moment resistant frames designed according to different editions of the Iranian code of Practice for seismic resistant design of buildings. Also, failure risk of a low and medium height frame which designed More
      In this paper, efforts are made to compare the safety of steel moment resistant frames designed according to different editions of the Iranian code of Practice for seismic resistant design of buildings. Also, failure risk of a low and medium height frame which designed for high and low seismicity regions according to three editions of the code are evaluated. First, the testing cases were designed and based on a simplified method the fragility functions of frames were evaluated. The probability of failure of frames was calculated by multiplying the fragility function and hazard curves in probabilistic manner. The results indicate that, apart from some exceptions, every edition of new code provides better safety for structures. However, within a single version of the code, the consistency of safety has not been maintained. The structures designed for low seismicity regions are more reliable than those which designed for high seismicity regions. Further research should address this issue and fix the possible. Manuscript profile
    • Open Access Article

      5 - Behavior Study of Cemented Specimen by Biological Technique after Disturbance
      Mohammad Reza Asgari Mohammad Azadi
      With the population growth and consequently the requirement for development of civil constructions, it is necessary to design appropriate foundations for resisting structural loads. Soil weakness in bearing capacity of geotechnical elements has forced the researchers to More
      With the population growth and consequently the requirement for development of civil constructions, it is necessary to design appropriate foundations for resisting structural loads. Soil weakness in bearing capacity of geotechnical elements has forced the researchers to continuously follow a solution to compensate for this deficiency. Within the past two decades, many studies have been carried out regarding the performance of this technique in optimization of the soil. One technique which is nowadays highly considered due to compatibility with the environment, high efficiency and low cost, is Biological Optimization Technique. One of the characteristics of this type of optimization is its ability for recovering after disturbance. In this research it has been tried to analyze the behavior of cemented specimens after disturbance and reconstruction. For this purpose, after construction of cubic specimens with dimensions of 2*6*6 cm and applying the disturbance and reconstruction, their shear strength under different vertical stresses has been evaluated by direct shear test. Manuscript profile
    • Open Access Article

      6 - The Effect of Viscous Dampers on Improvement of the Behavior of Tall Belt Truss Structures
      Nasser Gholaman Mohammad Ali Jafari
      Using energy absorption systems in the structures with malfunctioning components is of paramount importance. By absorbing the seismic energy, these systems help the components of the structure to remain resilient during earthquake. In the present study, viscous dampers More
      Using energy absorption systems in the structures with malfunctioning components is of paramount importance. By absorbing the seismic energy, these systems help the components of the structure to remain resilient during earthquake. In the present study, viscous dampers were applied in order to enhance the reactions of tall building with belt truss. To assess the response of a structure under earthquake loading conditions, we used the dynamic non-linear time-history analysis by the finite element method (FEM) using the ABAQUS software. Considering that the frequency content varies in earthquakes, each exert a different effect on the structure. For the evaluation of this parameter, seven accelerograms were used for the dynamic non-linear analysis. The studied tall buildings had 20, 30 and 40 floors and were selected without a damper and with viscous dampers so as to determine the effect of the number of floors on structural behavioral with and without dampers. X-braces were used in the structure, and the viscous dampers were applied within the horizontal braces. In addition, belt truss was used once in the last floor and again in the last and middle floors. According to the results, the structure’s response reduced due to the use of dampers or a second belt truss, so that the simultaneous addition of the middle belt truss and damper was associated with the highest reduction in the structure’s response (66.72%). However, this effect does not occur at all times, and the possibility must be considered for the structure before implementation. On the other hand, our findings suggested that the effects of the damper and middle belt truss on the decreased acceleration and maximum base shear would augment with increased height. Therefore, using dampers with middle belt truss is one of the most effectual techniques to reduce the structure response in tall buildings. Manuscript profile
    • Open Access Article

      7 - Lifelines Performance of the Mw 8.8 OffshoreBIOBÍO,Chile Earthquake
      Alex Tang
      The paper will provide a summary of all lifelines performance in this strong earthquake. The paper will discuss the damage, emergency response, and recovery of electric power, telecommunication, transportation (roads and bridges), seaports, airports, water and wastewate More
      The paper will provide a summary of all lifelines performance in this strong earthquake. The paper will discuss the damage, emergency response, and recovery of electric power, telecommunication, transportation (roads and bridges), seaports, airports, water and wastewater, and their facilities. The impact as a result of the lifelines service interruption will be discussed; most important is the discussion of lifelines interdependence. Each lifeline will be separated into its own section that presents the failure modes, emergency response, and recovery of service. Each section will end with observations and recommendations. Manuscript profile
    • Open Access Article

      8 - Modified Linear Approximation for Assessment of Rigid Block Dynamics
      Vahid Sharif
      This study proposes a new linear approximation for solving the dynamic response equations of a rocking rigid block. Linearization assumptions which have already been used by Hounser and other researchers cannot be valid for all rocking blocks with various slenderness ra More
      This study proposes a new linear approximation for solving the dynamic response equations of a rocking rigid block. Linearization assumptions which have already been used by Hounser and other researchers cannot be valid for all rocking blocks with various slenderness ratios and dimensions; hence, developing new methods which can result in better approximation of governing equations while keeping simplicity is necessary. In this paper, a new linear approximation is derived for solving the deferential equations of a rocking block in order to include wider range of blocks with various slenderness. The proposed method is verified by numerical solutions of the governing equations utilizing two methods of: average acceleration and fourth order Runge-Kutta. Verifications revealed more reasonable accuracy of the proposed method in comparison with the current linearization assumptions Manuscript profile
    • Open Access Article

      9 - Development of Fiber Reinforced SCM for Sustainable Construction
      Iman Mehdipour Nicolas Ali Libre Mohammad Shekarchia
      The sustainability of the built environment is increasingly coming to the forefront of infrastructure design and maintenance decisions. To address this, development of a new class of more sustainable cement-based materials is needed. Fiber reinforced self-consolidating More
      The sustainability of the built environment is increasingly coming to the forefront of infrastructure design and maintenance decisions. To address this, development of a new class of more sustainable cement-based materials is needed. Fiber reinforced self-consolidating mortar (FRSCM) was developed by optimizing the micromechanical parameters, which control composite properties in the hardened state, and the processing parameters, which control the rheological properties in the fresh state. The addition of fibers may take advantage of its high performance in the fresh state to achieve a more uniform dispersion of fibers, which can help to mitigate the shrinkage of the self-consolidating composite. In other words, fibers can have rheological and mechanical synergistic effects and that optimized fiber combinations can better increase mechanical performance while maintaining adequate flow properties for fiber reinforced self-consolidating mortar. In this study, effects of aspect ratio (l/d) and volume fraction (Vf) of polypropylene (PP) fiber on the free shrinkage and mechanical properties of FRSCM were investigated. Besides, the rheological properties of fiber reinforced SCMs are investigated by mini-slump and mini V-funnel tests. Nine mortar mixtures are prepared containing 0 to 0.7 percent of 6 and 12 mm length polypropylene fibers. The shrinkages of hardened mortar were measured since removing the molds and the measurements were continued up to six months. The results show that, the optimum volume fraction of polypropylene fiber content in SCMs to achieve appropriate rheological and mechanical properties is about 0.3% of the mixture volume. On the other hand, increasing the volume fraction and aspect ratio of PP fibers to about 0.7% causes the mechanical properties to drop considerably. This could be due to balling of fibers or fibers coagulation in the mixtures which decreases the mechanical properties. Manuscript profile
    • Open Access Article

      10 - A Mathematical Modeling for Plastic Analysis of Planar Frames by Linear Programming and Genetic Algorithm
      Leila Shahryari
      In this paper, a mathematical modeling is developed for plastic analysis of planar frames. To this end, the researcher tried to design an optimization model in linear format in order to solve large scale samples. The computational result of CPU time requirement is shown More
      In this paper, a mathematical modeling is developed for plastic analysis of planar frames. To this end, the researcher tried to design an optimization model in linear format in order to solve large scale samples. The computational result of CPU time requirement is shown for different samples to prove efficiency of this method for large scale models. The fundamental concept of this model is obtained from moment distribution method which is a safe theorem based method, so in this mathematical modeling, the objective is finding the largest load which ensures equilibrium and yield conditions. Contrary to moment distribution method, calculation of load factor and the value of moments in the elements are completely automatic and not to need user decision. As the objective function and constraints of this model are linear so it can be solved by linear programming (LP) software such as LINGO that is shown in this paper and also the model is solved by genetic algorithm (GA) to compare two solutions Manuscript profile
    • Open Access Article

      11 - Comparison Study on Neural Networks in DamageDetection of Steel Truss Bridge
      Hassan Aghabarati Mohsen Tabrizizadeh
      This paper presents the application of three main Artificial Neural Networks (ANNs) in damage detection of steel bridges. This method has the ability to indicate damage in structural elements due to a localized change of stiffness called damage zone. The changes in stru More
      This paper presents the application of three main Artificial Neural Networks (ANNs) in damage detection of steel bridges. This method has the ability to indicate damage in structural elements due to a localized change of stiffness called damage zone. The changes in structural response is used to identify the states of structural damage. To circumvent the difficulty arising from the non-linear nature of the inverse problem, three neural networks, Multi-Layer Perceptron Neural Network (MLPNN), Radial Basis Function Neural Network (RBFNN) and General Regression Neural Network (GRNN) are employed to simulate damage states of steel bridges. It was observed that the performance of all three networks is well and they have good agreement with actual results performed with Finite Element analysis. The efficiency of GRNN in structural identification is so good, although RBFNN has results close to GRNN and MLPNN results are satisfactory. All networks have good results while there is a little damage in structural members. Generally, results would have more error when damages in structural members extend. The engineering importance of the whole exercise can be appreciated once we realize that the measured input at only a few locations in the structure is needed in the identification process using neural networks. Manuscript profile
    • Open Access Article

      12 - Bearing Capacity Zoning of Shallow Foundations in District 1 in Shiraz Municipality Using Geographic Information System (GIS)
      Sara Afarid alireza Hajiani Boushehriana
      This research presents the geotechnical zoning map of district 1 in Shiraz municipality with focus on allowable bearing capacity of foundation based on data from 160 boreholes. For this purpose, the mechanical properties are determined according to the results of direct More
      This research presents the geotechnical zoning map of district 1 in Shiraz municipality with focus on allowable bearing capacity of foundation based on data from 160 boreholes. For this purpose, the mechanical properties are determined according to the results of direct shear, uniaxial, and SPT tests and then safe bearing capacity for strip foundations with widths of 1, 1.5, 2, and 2.5 m, and for Mat foundations with widths of 8, 12, 16, 20 and 24 m have been calculated. Finally, using ArcGIS software, the bearing capacity for the various widths was zoned and the zoning map of the allowable bearing capacity is provided by considering the allowable settlement. The zoning map shows that in the eastern part of the Shiraz municipality, the bearing capacity is greater than the other parts. The western and southern parts have a lower capacity than the northern parts. Manuscript profile
    • Open Access Article

      13 - The Effect of Soccer Ball Impulse on Lower Limbs of the Human Body
      Leila Shahryari Behtash JavidSharifi JavidSharifi Mohammad Ali Samianifar
      Despite the fact that soccer is one of the most popular sports in the world, little attention has been paid to this game scientifically which could otherwise provide a broad range of interesting outcomes. Sport equipment has a significant effect on how a game is played. More
      Despite the fact that soccer is one of the most popular sports in the world, little attention has been paid to this game scientifically which could otherwise provide a broad range of interesting outcomes. Sport equipment has a significant effect on how a game is played. Different features of the soccer ball such as its size, structure, weight and potential incoming pressure also affect the nature and quality of the game. Different models of soccer balls have been developed with the aim of increasing game quality and performance. Many scholars have investigated the displacements during typical soccer games caused by the ball impulse and the feet, but few studies have focused on the interaction between the ball and the feet. The aim of the present study is, thus, to investigate tension development and possible deformations caused by kicking the ball. Players who are well aware of soccer rules and have a little knowledge about soccer-induced injuries easily realize that the impulse of a non-standard ball considering its material, size or weight may severely damage the knees or other body parts. Due to the importance of the issue, to evaluate the impact of the soccer ball on the footballer’s feet, two finite element models of typical soccer balls have been studied with respect to the standard features of the real soccer ball in the three layers of leather, thread and rubber. The first model is proportional to the mass of the standard ball and the second incorporates a mass less than the standard level. Two models of bones are used in the present study: a single layer bone and a two-layer bone with cortical and cancellous tissues. For better understanding of the injuries resulting from the impulse from a non-standard ball, the used finite element software employs mechanic laws of sport biomechanics to provide better understanding of the details using mathematical modeling, computer simulation and experimental measurements. In this regard, this significant point is achieved through modeling the ball impulse to the feet which is quite complex and needs some simplification. As the soccer ball is flexible, most of the force is absorbed by the model’s flexibility. In the other model with a less flexible ball, the force absorbed by the bone is significantly more. Manuscript profile
    • Open Access Article

      14 - Assessment of Soil cohesion of Soils on Tunnel Excavation
      Mohammad Azadi
      Excess pore pressure under seismic loadings has always been a main concern in geotechnical engineering practices. Undergoing the phenomenon in a soil can cause the effective stress and hence the shear strength of the soil to decrease considerably and large deformations More
      Excess pore pressure under seismic loadings has always been a main concern in geotechnical engineering practices. Undergoing the phenomenon in a soil can cause the effective stress and hence the shear strength of the soil to decrease considerably and large deformations happen in the area. Generally, increasing the pore pressure occurs under the undrained condition. If it can be formed the drain conditions, its consequences decreases seriously. The damages caused by Excess pore pressure are divided in to two groups, surface damages and underground structures damages. Generally, first case is visible after the seismic loadings about which wide researches have been carried out. But in the second group, the lack of these occurrences and investigation problems cause the underground structures damages to be assessed less. There are several reports on devastations caused by excess pore pressure in the surrounding soil of the underground structures. As stresses and deformations of the tunnel lining increase, the surrounding soil of the tunnel is liquefied and large deformations are observed in the area. And if increasing the pore pressure occurs in the surrounding soil of the tunnel, improvement of the surrounding area of the tunnel, the stresses and deformations should be controlled to be set on the allowable limit. Therefore, evaluation of excess pore pressure effects on the tunnel lining can be regarded as an important issue. This paper is designed to focus on the topic. Manuscript profile
    • Open Access Article

      15 - Evaluation of Torsional Single Story Structure During Earthquake According to Canadian provision
      Seiyed Ali Haj Seiyed Taghia Masoud Ebrahimi Abdoulreza Sarvghad Moghadamc
      In this article, we tried to emphasis in how the range of torsionally stiff and flexible single story buildings works. The designed base was according to provisions of the Canadian standard, 2005 NBCC. The behavior of nonlinear dynamic time history of eight building mod More
      In this article, we tried to emphasis in how the range of torsionally stiff and flexible single story buildings works. The designed base was according to provisions of the Canadian standard, 2005 NBCC. The behavior of nonlinear dynamic time history of eight building models subjected to seven horizontal bi-directional ground motions compatible with design spectra are investigated. These models cover a wide range of torsionally stiff to flexible buildings. Response parameters are element ductility demand and building story drift ratio. These criteria are appropriate indices for structural and nonstructural damages, respectively. This investigation shows that the linear static and dynamic analysis of building codes such as the 2005 NBCC and its framework are not generally adequate for structures with extremely low torsional stiffness. The provisions in mentioned codes and its framework are able to limit ductility demand, but they do not limit drift to the allowable level for extremely torsional structure. Manuscript profile
    • Open Access Article

      16 - The Validity Assessment of Laboratory Shear Modulus Using In-Situ Seismic Piezocone Test Results
      Seyed Majdedin Mir Mohammad Hosseini A.A. Hajimohammadi
      Seismic piezocone device (SCPTu) together with Resonant Column and Cyclic Triaxial test apparatus are employed to measure small strain shear modulus (G0) of carbonate sandy and clayey soils of southern coasts of Iran. A large area of southern regions of Iran is formed f More
      Seismic piezocone device (SCPTu) together with Resonant Column and Cyclic Triaxial test apparatus are employed to measure small strain shear modulus (G0) of carbonate sandy and clayey soils of southern coasts of Iran. A large area of southern regions of Iran is formed from clay, silt and sand. In this study, maximum shear modulus that is derived from both field (by seismic piezocone) and laboratory (by Resonant Column and Cyclic Triaxial) tests on soil samples from the southern region, indicated a meaningful effect of sample disturbance. Results show that in laboratory tests, loose samples tend to become denser and therefore exhibit greater stiffness whereas dense samples tend to become looser, showing a reduction in stiffness. According to the results of the present study, there are narrow limits of soils shear moduli for which the laboratory tests and the field measurements yield approximately the same amounts. This limit of shear moduli is about 30-50(MPa) for clay deposits and 70-100 (MPa) for sandy deposits. Since the shear moduli of soils in small strains can also be computed from the shear wave velocity, also correlations based on parameters derived from SCPTu test for shear wave velocity determination of sandy and clayey soils of the studied area are presented. This study shows that shear wave velocity can be related to both corrected tip resistance and total normal stress. Regarding the shear moduli and the damping ratio, due to the disturbances of the stiff deposits in the sampling process and great deviations of laboratory results from field results, the laboratory measurements of these parameters out of the above limits are not recommended. Manuscript profile
    • Open Access Article

      17 - Effects of the Soil-Foundation-Structure Interaction on the Component Demand Modifier Factor of Concrete Gravity Beams based on ASCE 41-06 Standard
      A Azarbakht E Rajabi
      The aim of the present paper is to evaluate the influence of the Soil- Foundation- Structure Interaction (SFSI) effects on the component demand modifier factor of concrete gravity beams based on ASCE 41-06 standard. To this end, the beam on the nonlinear Winkler foundat More
      The aim of the present paper is to evaluate the influence of the Soil- Foundation- Structure Interaction (SFSI) effects on the component demand modifier factor of concrete gravity beams based on ASCE 41-06 standard. To this end, the beam on the nonlinear Winkler foundation approach is employed which is a simple and efficient method. At first, four sets of 3-, 6-, 10- and 15-storey concrete moment-resisting frames founded on soft, medium and hard soils are designed and analysed for the case of fixed-base and flexible-base assumptions. A comparison is then made between the results of the nonlinear response history analysis of each frame in the flexible-base and fixed-base conditions with the response based on the equivalent linear static approach. The findings show that the equivalent linear static approach loads for gravity beams, which are controlled by deformation actions, can lead to non-conservative predictions of seismic demand. Finally, a modified load combination is proposed to be used in the equivalent linear static approach to avoid this imperfection. Manuscript profile
    • Open Access Article

      18 - Prediction of mechanical and fresh properties of self-consolidating concrete (SCC) using multi-objective genetic algorithm (MOGA)
      Reza Jelokhani Niaraki Reza Farokhzad
      Compressive strength and concrete slump are the most important required parameters for design, depending on many factors such as concrete mix design, concrete material, experimental cases, tester skills, experimental errors etc. Since many of these factors are unknown, More
      Compressive strength and concrete slump are the most important required parameters for design, depending on many factors such as concrete mix design, concrete material, experimental cases, tester skills, experimental errors etc. Since many of these factors are unknown, and no specific and relatively accurate formulation can be found for strength and slump, therefore, the concrete properties can be improved to an acceptable level using the neural networks and genetic algorithm. In this research, having results of experimental specimens including soil classification parameters, water to cement ratio, cement content, super-lubricant content, compressive strength, and slump flow, using the MATLAB software, the perceptron neural network training, general regression neural network, and radial base function neural network are considered, and then, with regard to coefficient of determination (R2) criteria and mean absolute error, the above network Manuscript profile
    • Open Access Article

      19 - Performance of Mid-rise Buildings with Tubular Structure Under the Effect of Near Field Earthquakes
      Hooman Mazlooma Maryam Firoozi Nezamabadi
      The aim objective of this study is to investigate the effects of near-field earthquakes on the response of mid-rise buildings with tubular structure. For this purpose, a 20-story building with a square plan of six by six bays, all with 6 m span, and story height of 3.70 More
      The aim objective of this study is to investigate the effects of near-field earthquakes on the response of mid-rise buildings with tubular structure. For this purpose, a 20-story building with a square plan of six by six bays, all with 6 m span, and story height of 3.70 m is considered. Axial force of columns, shear lag, and inter-story drift values are used as the main response parameters. Nonlinear time history analyses (NLTHA) of the considered building were conducted by using once the two-component, and once more three-component accelerograms of both far- and near-field selected earthquakes for comparison. Numerical results of NLTHA show that inclusion of a vertical component of ground motion leads to around 17% and 32% increase, in average, in axial forces of side and corner columns respectively in case of far-field earthquakes. These increases were respectively 22% and 37% in case of near-field earthquakes. The vertical ground motion also leads to around 11% and 15% increase, in average, in shear lag of side and corner columns respectively in case of far-field earthquakes, and 13% and 19% increase in case of near-field earthquakes. The amount of increase in inter-story drift values due to the vertical ground motion was observed in range of 24% and 27% for far- and near-field earthquakes respectively. Manuscript profile
    • Open Access Article

      20 - Performance Evaluation of Viscoelastic and Friction Passive Damping System in Steel Structures
      Mohammad Taghi Kazemia Hosein Hoseini
      Additional dampers are employed in order to decrease the dynamic response of structure against the earthquake and wind loading recently. In this study, two types of systems related to waste of inactive energy, i.e. frictional damper which is categorized in dampers depen More
      Additional dampers are employed in order to decrease the dynamic response of structure against the earthquake and wind loading recently. In this study, two types of systems related to waste of inactive energy, i.e. frictional damper which is categorized in dampers dependent on movement and viscoelastic damper which is categorized in dampers dependent on velocity, in making steel structures resistant are investigated and evaluated. Results of structures with dampers (viscoelastic damper, friction damper and combination of both dampers) were compared with the results of structures without damper. Increasing trend in dissipating energy was observed. Then, the behavior of these dampers in frames of 4, 8 and 12 stories was studied by modeling the damper directly. The analyses were conducted via nonlinear time history technique and by using earthquake records (near fault and far fault) scaled with peak acceleration and SAP 2000 14.2.2 software. The results indicate the appropriate function of the selected dampers in controlling and decreasing the seismic responses of the structure. Given that in frictional dampers the maximum force created in the damper is specified, the use of this damper in resistance building of structures is very effective especially by considering the limitation of structure capacity. Manuscript profile
    • Open Access Article

      21 - The optimum configuration of FRP laminates of coupling shear wall concerning the load capacity
      Hamoon Abroon Shahrbijary Ali Delnavaz
      Using of CFRP carbon sheets because of their high strength, lightness and ease of use have been very expanded in retrofitting concrete members. Including shear walls systems FRP can be used in order to rebuild or maintain the strength of an aged structural member. Repai More
      Using of CFRP carbon sheets because of their high strength, lightness and ease of use have been very expanded in retrofitting concrete members. Including shear walls systems FRP can be used in order to rebuild or maintain the strength of an aged structural member. Repairing, or retrofitting of the intact structural member is conducted to enhance the structural resistance that was deteriorated due to the overloading, construction ignorance and so on. In this study, a model of coupled reinforced shear walls with changing the shape of CFRP fibers arrangement under lateral loading is considered. Then, the effect of coupled concrete compression shear wall resistance vary is investigated on the retrofitting. In all stages, the comparison among the proposed arrangement shape of CFRP fibers are accomplished in terms of lateral load carrying capacity of the specimens. Accordingly, the best form of fiber formation is recommended. Finally, it was concluded that the most optimistic fiber arrangement is fully covered and the next choice is vertically covered FRP arraignment. Manuscript profile
    • Open Access Article

      22 - A methodology for Determining the Seismic Vulnerability of Old Concrete Highway Bridges by Using Fragility Curves
      Araliya Mosleh jose jara Humberto Varum
      Past earthquakes have demonstrated that old RC bridges may be seismically vulnerable. Bridge responses during the last decades illustrated the necessity of the seismic assessment of bridges especially those which were designed with old codes. In this research an existin More
      Past earthquakes have demonstrated that old RC bridges may be seismically vulnerable. Bridge responses during the last decades illustrated the necessity of the seismic assessment of bridges especially those which were designed with old codes. In this research an existing concrete bridge representative of the most common bridges in the highway system in Iran are studied. Push over and nonlinear time history analyses using refined 3-D structural models are performed for each sample. Bridge structural systems are identified and quantified to establish a set of earthquake-site-bridge samples. The superstructure was assumed to remain elastic and the nonlinear behavior in piers was modeled by assigning plastic hinges in columns. The soil flexibility was considered by using elastic spring elements. Displacement ductility and peak ground acceleration (PGA) were selected as seismic performance indicator and intensity measure, respectively. Ten time history records from the past earthquakes were selected. They were scaled and applied incrementally to the 3-D model to evaluate seismic performance of the bridge. Furthermore, bridge damage states were defined and the probabilistic characteristics of structural capacity corresponding to each damage state were established. Then, the conditional probabilities of specific structural demand to exceed the structural capacity were computed and the results were displayed as fragility curves. Manuscript profile
    • Open Access Article

      23 - Effect of Reclaimed rubber Modification on the Rheological Properties and Rutting Resistance of Asphalt Binders
      Javad Poursharifi Poria Hajikarimi
      In this paper, the effect of reclaimed rubber modification on the rheological characteristics of asphalt binders is studied. Reclaimed rubber with the extent of 12, 16 and 20 is added to the neat asphalt binder and then shear complex modulus is obtained for neat and mod More
      In this paper, the effect of reclaimed rubber modification on the rheological characteristics of asphalt binders is studied. Reclaimed rubber with the extent of 12, 16 and 20 is added to the neat asphalt binder and then shear complex modulus is obtained for neat and modified asphalt binder via Dynamic Shear Rheometer (DSR) test. Using Christensen-Anderson- Marasteanu (CAM) model, master curves of shear complex modulus and phase angle are determined and compared for both neat and modified asphalt binders. Implementing master curves and the CAM model, a standard method for determining the high service temperature of asphalt binders is used and the effect of reclaimed rubber modification on rutting resistance is studied. Results have shown that adding reclaim rubber to the neat asphalt binder improves its rheological properties and rutting resistance. Manuscript profile
    • Open Access Article

      24 - Assessment of Tunnel Excavation on Surface Settlement
      Meysam Kalhor
      The expansion of underground structures is important in urban areas with high population density. In most large cities in the world, urban development is spreading along the structures. These structures are generally located at shallow depth; therefore study of shallow More
      The expansion of underground structures is important in urban areas with high population density. In most large cities in the world, urban development is spreading along the structures. These structures are generally located at shallow depth; therefore study of shallow tunnels in urban areas is critical for development. During the excavation of tunnels in urban areas, creating the asymmetric settlement of surface structures caused by changing stresses in the area due to the construction of underground structures is an issue to be regarded. In this research, the surface structure is considered as an overburden incurred on the tunnel, to assess the effects of tunnel excavation on the asymmetric settlement in the buildings to be built. For this purpose, a baseline model considered and the effect of the tunnel location are assessed into the existing buildings. Studies show the significant impact of the Location of tunnel on surface structure’s settlement than construction. The article is designed to provide the criteria can be generalized to all tunnels. The paper has tried to compare different modes of tunnel placement to get the best condition for the tunnel to the surface buildings, regarding the rate of asymmetry settlement foundation of Buildings Achieved. Manuscript profile
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      25 - Evaluation of Autogenous Shrinkage in High-Performance Concrete
      Jamal Ahmadi Reza Naghdi2
      Recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. However, high performance concretes have some problems. One of the problems is early-age cracking due to autogenous shrinkage. This study presents t More
      Recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. However, high performance concretes have some problems. One of the problems is early-age cracking due to autogenous shrinkage. This study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. According to this, effects of water/binder ratio, cement content, fine to coarse aggregate ratio and silica fume content were evaluated. From the results of this investigation, it can be concluded that the autogenous shrinkage strain of high strength concrete increases with reduction of w/b ratio. The results show also that the variation of cement content and fine to coarse aggregate ratio had only a limited effect on the autogenous shrinkage. Manuscript profile
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      26 - Rheological properties of self-consolidating concrete made by crushed waste tile aggregates
      Mahdi Mahdikhani Fatemeh Safikhani
      In recent decades, the use of self-consolidating concrete has become widespread. Hence, recognizing the various properties of self-consolidating concrete are essential. In this study, several mixture designs have been tested and final mixture design of crushed tile aggr More
      In recent decades, the use of self-consolidating concrete has become widespread. Hence, recognizing the various properties of self-consolidating concrete are essential. In this study, several mixture designs have been tested and final mixture design of crushed tile aggregates which were replaced by 0%, 25 %, 50%, and 100% volume percentage of natural aggregates were conducted. To evaluate fresh properties of SCC, slump flow and rheometer tests were carried out. Results show that the percentage of fine aggregates has a significant impact on the properties of self-consolidating concrete. In addition, the results of rheometer test show by increasing the percentage of recycled aggregates increases yield stress and plastic viscosity, significantly. Manuscript profile
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      27 - Performance of industrial facilities and lifelines during the October 23rd, 2011 Van, Turkey Earthquake
      Kiarash Nasserasadi Mehran Seyed Razzaghi
      Damage to essential facilities (e.g. lifelines and industrial facilities) due to extreme loads may cause remarkable indirect impact as well as direct physical loss. Hence understanding seismic performance of essential facilities is very important in high seismic risk re More
      Damage to essential facilities (e.g. lifelines and industrial facilities) due to extreme loads may cause remarkable indirect impact as well as direct physical loss. Hence understanding seismic performance of essential facilities is very important in high seismic risk regions. On October 23, 2011 an earthquake of magnitude Mw7.2 occurred in Van province in eastern Turkey. Several damages occurred at industrial plants. Damage to equipment and buildings caused work abandon in some industrial plants. In this paper the observed damage to essential facilities such as transportation systems, silos and gas stations are presented. Manuscript profile
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      28 - Deformation Performance of the Karkheh Earth Dam with Mixed and Pure Clay Coreunder Seismic Excitations
      Majdedin Mir Hosseini R. Bahrami M. AsadolahiPajouh
      The number of constructed dams has been largely increased due to high demands of water supplies, and earth dams are the most common types since they are more compatible to the environment. Nevertheless, the stability of these important structures during earthquakes has More
      The number of constructed dams has been largely increased due to high demands of water supplies, and earth dams are the most common types since they are more compatible to the environment. Nevertheless, the stability of these important structures during earthquakes has to be carefully evaluated and guaranteed. In the past, earth dams usually designed with pure clay core, but in recent decades they are widely designed and constructed with mixed clay core due to their better performance against vibrations particularly earthquake loadings. This paper evaluates the displacement performance of the Karkheh Large Embankment Dam with mixed- clay core, recently constructed in south-western part of Iran, under earthquake motions and compares the dynamic analyses’ results with those of pure-clay core. In this work, the Karkheh Dam with both mixed and pure clay core is numerically modeled using the FLAC 4.0software. After calibrating the model and completing the static and dynamic analyses under different excitations, belonged to some heavy past earthquakes, the results in terms of the maximum settlements, horizontal displacements of upstream and downstream shells are estimated, compared and discussed. Based on the obtained results, it is noted that the dynamic performance of earth dams with mixed-clay core is more desirable than that of pure-clay core. It is also observed that the seismic settlements of the dam with pure-clay core averagely show an increase of 20 percents compared with that having the mixed-clay core. Manuscript profile
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      29 - Soil-Interaction of Intake Pressure Tunnels under Ground Strength Reduction Conditions due to Cracking of the Lining(Case study: Dasht-e-Abbas intake pressure tunnel)
      seysd majddin Mir Mohammad Hosseini P Malek Mohammadib M. Asadolahi Pajouhc
      The induced cracks on the concrete lining of the intake pressure tunnels may cause the water seep into the surrounding media leading to develop a hydro pressure on the external surface of the lining. In the common design practice, the lining can be designed to tolerate More
      The induced cracks on the concrete lining of the intake pressure tunnels may cause the water seep into the surrounding media leading to develop a hydro pressure on the external surface of the lining. In the common design practice, the lining can be designed to tolerate with this pressure using the Schleiss method. However, when the tunnel is constructed above the underground water, the seepage may cause the strength of the ground to reduce the amount of which may be considerable in some water sensible soils. In this paper, the finite element package of PLAXIS has been used to do the non-linear analysis of an intake pressure tunnel located inside a mudstone soil. The stress-strain model for the lining is taken linear elastic and for the soil is the elasto-plastic Mohre-Columb. The analysis is carried out by developing a 2D numerical model for an area of 100X73 meters. Consequently, the optimum lining is designed while the soil strength reduction occurs due to the seepage of water through the cracks in the lining. The results of numerical analysis are compared with that obtained from Schleiss common method of designing. Finally, a series of parametric studies are carried out and some important points and comments are suggested for designing of intake pressure tunnels facing the same condition. Manuscript profile
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      30 - An Investigation into a Geocell-reinforced Slope in the Unsaturated Numerical Model
      Behnam Mehdipour Hamid Hashemalhosseini Bahram Nadi Masoud Mirmohammad Sadeghi
      Considering unsaturation conditions of soil significantly helps to produce relatively real results. Numerical methods have been assumed as conventional methods in soil mechanics to examine soil behavior. However, the accuracy of numerical methods dramatically depends on More
      Considering unsaturation conditions of soil significantly helps to produce relatively real results. Numerical methods have been assumed as conventional methods in soil mechanics to examine soil behavior. However, the accuracy of numerical methods dramatically depends on applying the appropriate behavioral model to solve problems. One of the known elastoplastic models for unsaturated soils is the Barcelona Basic Model which is added to FLAC2D software through codification. Geocell-reinforced slope functions as a beam in the soil due to the three dimensional nature of the reinforcement, i.e. height is included. Furthermore, the reinforcement causes a reduction in slope displacement and an increase in the factor of safety of slope due to its bending characteristics including moment of inertia and consequently bending strength. Moreover, soil unsaturated conditions are applied to the modelling and suction variations in soil are incorporated. This makes the maximum horizontal displacement of slope occur in the upper part of the Geocell layer while the horizontal displacement values for the slope height are substantially reduced below the Geocell layer. Increasing suction, geocell axial force declines by at most 18.5%. As overhead pressure increases, there is an increase in the force concentrated at the soil-geocell interface and the tensile force is consequently enlarged in reinforcements. Manuscript profile
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      31 - New Approach for Approximation of Dispersivity in Porous Media
      Mohammad Reza Fadaei Tehrani Raheleh Feizy Homayoun Jahanian
      This paper presents a simple yet powerful original approach for approximating dispersivity in porous media. The key to this approach is both use of least-squares criterion and image processing technique. Two dimensional transparent models, including horizontal and verti More
      This paper presents a simple yet powerful original approach for approximating dispersivity in porous media. The key to this approach is both use of least-squares criterion and image processing technique. Two dimensional transparent models, including horizontal and vertical configurations, under different combinations of grain sizes and pore velocities, experimented. Concentration data were obtained on a 0.5×0.5 mm grid, which represents approximately 1.8×105 measuring points. Estimates of the longitudinal and transverse dispersivity are obtained for each experiment in three time step, and discussed. Acquired results revealed that presented procedure successfully determine dispersivity coefficients and the maximum error of estimation is 4 to 7%. Furthermore, calculated disperssivity varied from 0.001 to 0.003 m corresponding to grain sizes that agree with literature. Manuscript profile
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      32 - Neural Prediction of Buckling Capacity of Stiffened Cylindrical Shells
      Mehran Seyed Razzaghi N. Rahmani
      Estimation of the nonlinear buckling capacity of thin walled shells is one of the most important aspects of structural mechanics. In this study the axial buckling load of 132 stiffened shells were numerically calculated. The applicability of artificial neural networks ( More
      Estimation of the nonlinear buckling capacity of thin walled shells is one of the most important aspects of structural mechanics. In this study the axial buckling load of 132 stiffened shells were numerically calculated. The applicability of artificial neural networks (ANN) in predicting the buckling capacity of vertically stiffened shells was studied. To this end feed forward (FF) multi-layer perceptron (MLP) neural networks were used. The shell height (H), shell diameter (D), shell thickness (t), width (b), thickness of stiffeners (ts), and unstiffened length of the cylinder (l) were considered as the input vector; the relative buckling capacities of stiffened shells to unstiffened ones (Pcr/Pcr0) were considered as the output of the MLP networks. The back propagation algorithm was used to train the networks. Different structures of ANN were trained by 100 of the outputs of the numerical analysis and tested by 32 remains. The best ANN structure was selected based on the mean square error (MSE) and correlation coefficient (R2). The results of this study revealed that MLP neural networks can remarkably predict the axial capacity of stiffened shells. A parametric study on the buckling loads of the stiffened shells was performed by using the neural prediction and FEM. Manuscript profile
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      33 - Conceptual Analysis and Design and Experimental Construction of a Portable Emergency Relief Bridge
      Ehsan Soltani Shahrokh Rezaei
      10.22094/jseg.2022.695371
      For a long time, our country has faced natural disasters. In recent years, it has imposed various levels of damages on the country, including those caused by wars (military maneuvers) and natural disasters (earthquakes such as Rudbar Manjil, Bam, and Azgeleh), and flood More
      For a long time, our country has faced natural disasters. In recent years, it has imposed various levels of damages on the country, including those caused by wars (military maneuvers) and natural disasters (earthquakes such as Rudbar Manjil, Bam, and Azgeleh), and floods in cities and regions). Every year, severe floods, hurricanes, explosions, and terrorist attacks cause great suffering for millions worldwide. In a disaster, whether natural or humanitarian, it is vital to provide immediate help to those affected, but relief can often be severely interrupted, significantly if the infrastructure is damaged and the transport network is disrupted. Here, the bridge will be constructed from nonidentical prefabricated elements based on modularity. Construction of modules and final assembly is done off-site (in a factory). Because it can be deployed on-site, it transported the completed bridge in a compact form. SAP2000 software evaluated an emergency bridge's seismic design and performance using nonlinear static and dynamic analysis to save lives in the shortest amount of time, cost, construction, and installation, while also considering the structure's performance. Also, its portability is the goal of this structure. In this system, space structures were used to design the project, absorbing much energy outside their elastic range and was innovative. As a result, the ultimate bearing capacity of the space trusses will depend on the structure's geometry, the position of the supports, and the displacement load response of each member. Manuscript profile
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      34 - The Stability Assessment of Dasht-e-Abbas Pressure Intake Tunnel Subjected to Ground Strength Reduction-Iran
      S. M Mir Mohammad Hosseini P Malek Mohammadi M Kargar
      The hydraulic pressure is one of the most important factors in the design of pressure intake tunnels. Since the surrounding media cannot usually resist the high internal pressure of these tunnels, they are usually finished with an adequate lining mostly of reinforced co More
      The hydraulic pressure is one of the most important factors in the design of pressure intake tunnels. Since the surrounding media cannot usually resist the high internal pressure of these tunnels, they are usually finished with an adequate lining mostly of reinforced concrete, which is an interaction problem between water, soil or rock and concrete lining. Although reinforcing the concrete lining may reduce the width and number of the developed cracks in the lining, the penetration of water into the surrounding media can still happen due to high water pressure in the tunnel. Thus, it may lead to the development of hydro pressure on the external surface of the lining. There are some theoretical methods that are developed for the design of tunnel lining in this condition. When the tunnel is located above the underground water table, the seeping water may lead to strength reduction of the adjacent soils, particularly when the ground, like the mudstone layers existing in Dasht-e-Abbas region, south-west of Iran, is cohesive and consists of soils that are susceptible to water. In this paper, the hydrostatic interaction between soil and concrete lining of Dasht-e-Abbas pressure intake tunnel has been investigated when the shear strength parameters of the mudstone layers decrease due to the seepage of water to the surrounding media. To evaluate the stability of the tunnel, a two dimensional numerical simulation is developed using the finite element code called PLAXIS and interaction analyses are carried out. The analyses are done in stages to assess the maximum internal forces induced in the lining. The structural stability of the tunnel is evaluated and discussed in this condition. Based on the obtained results, it is noted that for more realistic understanding of the behavior of infrastructures like pressure intake tunnels under various conditions, numerical analyses should also accompany experimental and analytical approaches such as Schleiss method which is described in this paper, especially for tunneling in media that is susceptible to water and ground strength reduction. The numerical analysis results show a considerable increase in the lining internal forces when subjected to the reduction of ground strength. However, the tunnel structure is still stable under the effect of surrounding ground degradation with the constructed lining specifications. Manuscript profile
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      35 - Preliminary evaluation of induced seismicity at the Karkheh dam site in southwest Iran
      The reservoir-induced seismicity (RIS) at the Karkheh dam site with a reservoir capacity of about 7.4x109 meters is investigated. Based on the assessment of the seismicity of the dam site in equal time periods before and after reservoir impoundment, it was found that th More
      The reservoir-induced seismicity (RIS) at the Karkheh dam site with a reservoir capacity of about 7.4x109 meters is investigated. Based on the assessment of the seismicity of the dam site in equal time periods before and after reservoir impoundment, it was found that the number of earthquakes have been tripled after impoundment, while their magnitudes and focal depths become smaller. The average earthquake depth before the impoundment was about 40 km whereas it decreased to about 23 km after that. Based on this study, it is concluded that RIS is happening in the Karkheh dam site and it is necessary to study the possible associated hazards. Manuscript profile
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      36 - Assessment of the Drain Conditions on Variations of the Pore Pressure in Surrounding Soil of the Tunnel
      Mohammad Azadi Azadi S.M Mir Mohammad Hosseinib S.M. Nasimifar M Pouranian
      Excess pore pressure under seismic loadings has always been a main concern in geotechnical engineering practices. The phenomenon in soil can cause an effective stress and hence cause the shear strength of the soil to decrease considerably and large deformations to occur More
      Excess pore pressure under seismic loadings has always been a main concern in geotechnical engineering practices. The phenomenon in soil can cause an effective stress and hence cause the shear strength of the soil to decrease considerably and large deformations to occur in the area. Generally, increases in pore pressure occur in un-drained conditions. If it is formed, its consequences decrease seriously. There are several reports on devastations caused by excess pore pressure in the surrounding soil of the underground structures. As stresses and deformations of the tunnel lining increase, the surrounding soil of the tunnel is liquefied and large deformations become observable. If an increase in the pore pressure occurs in the surrounding soil of the tunnel, which is an improvement of the surrounding area of the tunnel, then stresses and deformations should be set on the allowable limit. Therefore, evaluation of excessive pore pressure effects on the tunnel lining can be regarded as an important issue and this paper is designed to focus on precisely this topic. Manuscript profile
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      37 - NEW RCS Frame Connection in Structures
      Hasan Aghabarati K. Parhizkar
      Hybrid moment frame come together with reinforced concrete columns with structural steel beams (RCS). This Composite system provides several key advantages over current steel or concrete moment resisting frame. Past studies have shown this system to be efficient in both More
      Hybrid moment frame come together with reinforced concrete columns with structural steel beams (RCS). This Composite system provides several key advantages over current steel or concrete moment resisting frame. Past studies have shown this system to be efficient in both design and building stage while able to keep sufficient strength and necessary ductility in seismic zone.Although past researches controlled use of this composite structural system in the United States for none and low-seismic hazard zones, this paper considers some of the latest provisions on RCS systems, which is to provide support in the development of performance based earthquake engineering. Also paper introduces a type of rigid steel beam to RC column connection and discusses its hysteresis curvature behavior and response modification coefficient of this hybrid system. Manuscript profile
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      38 - Application of Fuzzy Modeling to Earthquake Engineering: Seismic Performance of Cylindrical Tanks
      Milad Ahmadi Brace
      The fuzzy logic concept provides a natural way of dealing with problems in which the source of imprecision is an absence of sharply defined criteria rather than the presence of random variables. The fuzzy approach considers cases where uncertainties play a role in the c More
      The fuzzy logic concept provides a natural way of dealing with problems in which the source of imprecision is an absence of sharply defined criteria rather than the presence of random variables. The fuzzy approach considers cases where uncertainties play a role in the control mechanism of the concerned phenomena. Fuzzy modeling includes fuzzification, fuzzy analysis and defuzzification. In this paper, the basic of fuzzy theory and all three steps are discussed and a tangible example which includes the application of fuzzy modeling in dealing with uncertainty in data to produce fragility curves is demonstrated step by step. The results are compared to other results of recent studies. Manuscript profile
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      39 - The Behavior of Type of RC Column-to-Steel Beam Connections and Scrutiny Of Behavior Coefficients
      Hassan Aghabarati Mehran Seyed Razzaghi Kavian Parhizkar
      (RCS) frames which are systems that dwell of concrete columns and steel beams , by optimizing the act of compressive strength of concrete and bending strength of steel due to not only a decrease in building weight in comparison to concrete structures but also having a b More
      (RCS) frames which are systems that dwell of concrete columns and steel beams , by optimizing the act of compressive strength of concrete and bending strength of steel due to not only a decrease in building weight in comparison to concrete structures but also having a better action in long spans frames . In this paper for analysis RCS behavior, a category of nonlinear Push Over analyses were achieved on typical low to mid-rise RCS buildings. 1,2,3,4 and 5 span frames with span length of 6 meters in 1 to 5 stories were elected for this project. The systems were controlled by using FEMA-273 and ATC-40 codes. Manuscript profile
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      40 - Offgas Treatment Approaches By Focusing On Biofiltration Methods in Asphalt Factories
      saeed nemati
      In the considered foundry emits offgas containing VOCs (especially ethanol). In order to reduce the VOC content, a compost based biofilter has been installed. In this approach, the polluted air stream enters a pre-conditioning chamber where temperature and humidity is a More
      In the considered foundry emits offgas containing VOCs (especially ethanol). In order to reduce the VOC content, a compost based biofilter has been installed. In this approach, the polluted air stream enters a pre-conditioning chamber where temperature and humidity is adjusted for asphalt factories. Biofilteration has already been well established as an air pollutant control alternative. There are some physical, chemical and biological parameters which influence biofilter performance such: filter media , oxygen availability , moisture content , pH and etc. . In the considered factory emits offgas containing VOCs (especially ethanol) . It shows that may be there are still some VOCs in offgas which are not degraded by biofiltration. Biofiltration is not a suitable choice for treating the offgas of the certain foundry. Optimum off-gas temperature is between 25 and 37 DC but in this case, the bed temperature is less/more than the optimum range. In considered situation, it may be necessary to substitute biofiltration by another technology which can remove VOCs and odoriferous compounds completely. Different factors may affect the decision on application of these technologies, and also the effectiveness and cost of these technologies: VOC concentration, VOC species, and presence of halogenated VOCs, presence of catalyst poisons, particulate loading, moisture content, gas flow rate, and ambient temperature. Manuscript profile
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      41 - The Behavior of Type of RC Column-to-Steel Beam Connections and Scrutiny Of Behavior Coefficients
      Hassan Aghabarati Mehran S. Razzaghi Seyed Razzaghi Kavian Parhizkar
      (RCS) frames which are systems that dwell of concrete columns and steel beams , by optimizing the act of compressive strength of concrete and bending strength of steel due to not only a decrease in building weight in comparison to concrete structures but also having a b More
      (RCS) frames which are systems that dwell of concrete columns and steel beams , by optimizing the act of compressive strength of concrete and bending strength of steel due to not only a decrease in building weight in comparison to concrete structures but also having a better action in long spans frames . In this paper for analysis RCS behavior, a category of nonlinear Push Over analyses were achieved on typical low to mid-rise RCS buildings. 1,2,3,4 and 5 span frames with span length of 6 meters in 1 to 5 stories were elected for this project. The systems were controlled by using FEMA-273 and ATC-40 codes. Manuscript profile
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      42 - Quasi-static Axial Compression of thin-walled Circular Composite Tubes
      Mohammad Mahdi Kheirikhah Sajjad Dehghanpour Mohsen Rahmani
      Assessing the behavior of composite structures which are subjected to impact loads is one of the important subjects in the field of mechanical sciences. Using thin-walled tubes which collapsed and absorbed the impact energy is a well-known method to prevent damages to t More
      Assessing the behavior of composite structures which are subjected to impact loads is one of the important subjects in the field of mechanical sciences. Using thin-walled tubes which collapsed and absorbed the impact energy is a well-known method to prevent damages to the other parts of the structures. In this paper, deformations, crushing length, peak load, mean force and energy absorption capacity of thin-walled circular composite tubes are investigated both experimentally and numerically. In order to experimental study, three circular composite tubes were fabricated and subjected to quasi-static axial load. Also, a finite element model was constructed and analyzed under same conditions using FEM27 and LS-DYNA software packages. The results of simulations are in good agreement with the experimental data and show that the section geometry has considerable effect on the energy absorption. The circular composite tube has the most energy absorption capacity and the most average force among all investigated sections. Manuscript profile
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      43 - Probabilistic Evaluation of Seismic Performance of RC Bridges in Iran
      Mehran Seyed Razzaghi M. Safarkhanlou
      Many existing bridges were designed without adequate consideration of seismic risk. The full or partial collapse of even one major bridge in a city or community would have destroying results. There has been focuses on developing fragility-based seismic vulnerability of More
      Many existing bridges were designed without adequate consideration of seismic risk. The full or partial collapse of even one major bridge in a city or community would have destroying results. There has been focuses on developing fragility-based seismic vulnerability of existing usual bridges in Iran or support decision making on seismic upgrade. This article focuses on developing performance based seismic fragility curves for typical RC bridges in Iran. Ground motions compatible with the seismic hazard were used as input excitations for bridge vulnerability assessment. The fragility curves thus developed will quantify the vulnerability of existing RC bridges and help in proper decision making to increase the safety for humans and the serviceability of essential facilities. Results obtained from this study show that the properties of materials have a significant effect on the damage probability of the bridges. The findings can serve as a guide to declare the impact of seismic vulnerability on the bridges. Manuscript profile
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      44 - Analyzing the plan accommodation and constructing the buildings components by using analytical hierarchy process AHP, the case study of Qazvin province in Iran
      Amir Hossen Hashemi Mohammad Reza Sadeghi Moghaddam Amir Yavari
      The quick growth of the population and the increasing need of the demands for developing caused the construction and production process formed with increasing technology than the past, this speeding in construction process caused the construction quality and executing e More
      The quick growth of the population and the increasing need of the demands for developing caused the construction and production process formed with increasing technology than the past, this speeding in construction process caused the construction quality and executing engineering points and the lack of accommodation of construction to the plans increase more. So the purpose of this article is the definition and arrangement of control checklist and planning basic criterions and indices which are very important in an agent construction management system. According to the fact that checklist controlling are conducted in Qazvin city in field studies and the checklists have been arranged qualitatively, so for determining the amount of plan accommodation and the construction, the hierarchical analysis method AHP is used. And the checklists options have been used as modeling indices and finally according to the results of modeling this result is derived that in most of the cases the indices are accommodating with the plans but in some cases these principles became observable significant. Manuscript profile
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      45 - Development of Seismic Criteria for Seismic Responses of Regular and Irregular Structures in Plan considering Vertical Component of the Near-field Records
      Maryam Firoozi Nezamabadi Fariborz Yaghoobi Vayeghan
      Field observations of the incurred damages to the buildings and bridges due to earthquakes in near field show there are various failure modes which are in relation to the forces caused by vertical component. While vertical component of earthquake for ordinary buildings More
      Field observations of the incurred damages to the buildings and bridges due to earthquakes in near field show there are various failure modes which are in relation to the forces caused by vertical component. While vertical component of earthquake for ordinary buildings in most seismic regulations and standards is not considered. Therefore, in the current study the effects of vertical and horizontal components of earthquake on regular and mass asymmetric structures are investigated simultaneously. The study considers a model of one-story structure with 3 degrees of freedom, lateral displacement, torsional displacement of roof level and vertical displacement, on a rigid foundation. It is concluded that for all such structures in the near-fault zones, the effect of vertical component must be considered. In case of stiff structures, the effect of the force on displacement of such structures is of importance and the effect of vertical component can be disregarded. The use of vertical design response spectrum to calculate the vertical forces caused by near field earthquakes is also recommended. Manuscript profile
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      46 - Analysis of support pressure for stabilization of rock blocks in the Zaker tunnel
      Vahid Hosseini Toudeshki
      This paper presents the results of engineering geological studies of rock blocks along a road tunnel in NW Iran. The tunnel is to cross the Western Alborz Mountain Range through 530 m in length with 11.2 m span and 8 m height. Eocene tuffs and andesites crop out in whol More
      This paper presents the results of engineering geological studies of rock blocks along a road tunnel in NW Iran. The tunnel is to cross the Western Alborz Mountain Range through 530 m in length with 11.2 m span and 8 m height. Eocene tuffs and andesites crop out in whole of the tunnel route. Numerical analyses are done using, a 3D stability analysis and visualization program, called Unwedge that studies pyramidal blocks and supplies an easy-to-use, graphical environment for data entry and visualization. The analysis of support pressure and the sensitivity analysis are done in the different units of the tunnel and the most critical mode of joints combination and the most optimal excavation direction in each of the units is determined. From this analysis, it is possible to ascertain the support pressure for stabilize the rock blocks as a function of the trend and plunge of the tunnel axis. Three-dimensional diagrams have been used to illustrate how the support pressure assembly might affect the design of an excavation. Manuscript profile
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      47 - A Numerical Evaluation of Seismic Response of Shallow Soil Deposits
      S. M. Babaee seyed mjddin Mir Mohammad Hosseinib
      This paper employs one-dimensional numerical ground response analysis models to investigate seismic response of shallow cohesive and non-cohesive soil deposits on vertical propagation of horizontal shear waves. Soil response is modelled by traditional equivalent-linear More
      This paper employs one-dimensional numerical ground response analysis models to investigate seismic response of shallow cohesive and non-cohesive soil deposits on vertical propagation of horizontal shear waves. Soil response is modelled by traditional equivalent-linear (EL) frequency-domain analysis using DEEPSOIL software and nonlinear (NL) time-domain analysis using OPENSEES software. The analysis is performed on soil columns of different heights to account for depth dependency of responses. Input rock outcropping motions are selected from far-field and near-field time histories and scaled to various shaking levels to evaluate soil nonlinearity level. The results show that the shallow soil deposits have capability of amplifying the input motion considerably. Moreover, With increasing soil depth, greater damping and shifting in the dominant periods of the computed spectra occur and maximum value of spectrums increases. These results for shallow soil deposits, highlight the need to consider the full depth of the soil column to perform local ground response analysis. Manuscript profile
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      48 - Assessment of ASCE 41-06 Pushover Procedure in Performance Evaluation of Concrete Vertical Irregular Buildings
      Ehsan Danesh Dezfuli armin Aziminejadb
      Irregular buildings make up a large portion of urban infrastructure. Presence of irregularities can be due to architectural and user changes in building stories. Main objective of this article is evaluate seismic performance of structures with vertical irregularities. S More
      Irregular buildings make up a large portion of urban infrastructure. Presence of irregularities can be due to architectural and user changes in building stories. Main objective of this article is evaluate seismic performance of structures with vertical irregularities. Seismic responses are obtained by enveloping peak inelastic responses resulting from pushover analyses according to provided pattern in ASCE/SEI 41-06standard. To verify and appraise procedure, it is applied to 10, 15, and 20-storey models with irregular distribution of mass, stiffness and strength along height. Results from the pushover procedure are compared with results obtained by nonlinear response history analysis (NL-RHA). Results of research reveal that seismic response of building structures is more sensitive to stiffness irregularities than to mass irregularities and strength irregularities. Nonlinear static procedure that proposed in standard can predict to a reasonable accuracy peak inelastic responses, such as plastic rotations of hinges, story drifts and shear stories in vertically irregular structures Manuscript profile
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      49 - Numerical Modeling of the Effect of Geocell Elements’ Dimensions on Behavior of Circular Footings
      Soheil Ghareh
      Use of auxiliary elements in refining and betterment of engineering properties of soil have gained attention since a long time ago. Nowadays the effectiveness and capability of the soil reinforcing technique for giving proper practical solutions in various projects have More
      Use of auxiliary elements in refining and betterment of engineering properties of soil have gained attention since a long time ago. Nowadays the effectiveness and capability of the soil reinforcing technique for giving proper practical solutions in various projects have resulted in this technique quickly gaining a place in geotechnical engineering. In this paper, the results of laboratory studies on such characteristics as width and height of the geocell element on load-bearing capacity and settlement of footings have been modelled numerically. It should be noted that the laboratory studies have been carried out in the uniaxial apparatus and analytical studies have been carried out utilizing the finite element software ABAQUS 6.11. by investigating the results it can be seen that in the case of using a geocell element in reinforcing the soil, the load-bearing capacity of the footing increases 1.65 times in comparison with the non-reinforced sample, while settlement in the reinforced footing – with geocell – is only 1.15 times more than the non-reinforced footing. Furthermore when the increase in load-bearing capacity of the footing has a significant importance, the best scenario is increasing the height of the geocell element. But when the footing’s settlement is of significant importance, we can have more effective results by changing the width of the geocell element. By comparing the results from numerical and laboratory studies, an appropriate agreement is observed and in all cases the analytical studies have more conservative results compared to the results from laboratory studies. Manuscript profile
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      50 - Seismic Performance of Torsionally Stiff and Flexible Single Story Buildings Designed Based on Iranian Seismic Code(Standard 2800)
      Seiyed Ali Haj Seiyed Taghia A.S. Moghadam
      This paper examines differences in performances of a range of torsionally stiff and flexible single story buildings designed with the provisions of Iranian Standard 2800. Seismic nonlinear dynamic time history behavior of eight building models subjected to seven horizon More
      This paper examines differences in performances of a range of torsionally stiff and flexible single story buildings designed with the provisions of Iranian Standard 2800. Seismic nonlinear dynamic time history behavior of eight building models subjected to seven horizontal bi-directional design spectra compatible ground motions are investigated. These models cover a wide range of very torsionally stiff to very flexible buildings. Response parameters are element ductility demand and building story drift ratio. These criteria are appropriate indices for structural and nonstructural damages, respectively. This investigation shows that the linear static analysis of building code such as Iranian Standard 2800 is not generally adequate for structures with very low torsional stiffness. Manuscript profile
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      51 - Evaluation of Influencing Factors on the Pull-out Behavior of Suction Caissons
      Adel Asakereh Abdol Hamid Kamali
      Suction caisson is a type of floor foundation for the offshore structures that is also called suction pile, bucket foundation, suction anchor, or sometimes ridge foundation depending on its application. In two past decades, this type of foundation has been widely used a More
      Suction caisson is a type of floor foundation for the offshore structures that is also called suction pile, bucket foundation, suction anchor, or sometimes ridge foundation depending on its application. In two past decades, this type of foundation has been widely used around the world as the fixed offshore foundation, anchor of the floating platforms, as well as the foundation of other marine structures such as the offshore wind turbines. Suction caisson is a metal (or sometimes concrete) hollow cylinder that is open from its bellow while it is top is being closed by flat or dome plates. This type of caisson is called suction caisson mainly because its installation is done by suctioning their water outside after drainage. In this research, numerically study the effective factors on the pullout behavior of the suction caissons. The analyses conducted in two-dimensional form on the drainage condition on clay soil. The results of the analysis show that the strength parameters of the soil are significantly effective on the pullout capacity of the suction caisson. Manuscript profile
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      52 - The Effects of Shallow Tunnels on Nearby Structures
      Mohammad Azadi A. Zahedi
      Nowadays, underground structures play vital role in developing different countries. Such structures are constructed in many civil activities such as development of road and railways, subways, water, gas and sewage lines, underground subways, nuclear wastes land filling, More
      Nowadays, underground structures play vital role in developing different countries. Such structures are constructed in many civil activities such as development of road and railways, subways, water, gas and sewage lines, underground subways, nuclear wastes land filling, fuel storage and military installations. With an appropriate drilling method being selected, instabilities created in tunnels may be controlled, the volume of maintenance systems required in structures may be decreased, and extra costs arising from it may be decreased as well. Excavation of surface tunnels may bring about changes on the surface and in the adjacent structures. Settlement on the surface and instabilities in adjacent structures as a result of stress induction are among the most important changes of this kind. Plaxis software has been used in the research to evaluate the technical parameters of tunnel such as tunnel diameter, tunnel depth from the earth surface, drilling method and distance from adjacent structures. Meanwhile it investigates the effects of urban tunnel drilling as lifelines on adjacent structures and render the results in the form of a diagram. Manuscript profile
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      53 - An Experimental Study on Effect of Waste Tire Rubber on the Fresh and Hardened Behavior of Self-compacting Concrete
      Mohammad saleh Moghaddam Saman RahatDahmardeh mohammad hassan Moghaddam
      The development of environmentally accepted methods of used tire disposal is one of the greatest challenges that waste management experts face today. Use of waste rubber particles as aggregate in self-compacting concrete is a suitable solution for the environmental haza More
      The development of environmentally accepted methods of used tire disposal is one of the greatest challenges that waste management experts face today. Use of waste rubber particles as aggregate in self-compacting concrete is a suitable solution for the environmental hazards of waste tires being produced on a large scale. The aim of this work is to investigate the influence of the size of waste rubber particles and the waste replacement volume on the fresh and hardened properties of self-compacting waste rubberized concrete (SCWRC). Tire rubber particles were used in two groups to replace 5%, 10%, 15% and 20% of fine (GRSCC) and coarse (CRSCC) aggregate, separately. The water to cement ratio used in the concrete mixes was 0.42. The experimental results showed that the workability, water absorption and mechanical properties such as compressive and flexural strengths and ultrasonic pulse velocity of SCWRC reduced with the increase of rubbercontent. Manuscript profile
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      54 - Structural Damage Identification of Plate Structures based on Frequency Response Function and Natural Frequencies
      A Esfandiari
      In this paper, a structural damage identification method (SDIM) is developed for plate-like structures. This method is derived using dynamic equation of undamaged/damaged plate, in which local change in flexural rigidity is characterized utilizing a damage distribution More
      In this paper, a structural damage identification method (SDIM) is developed for plate-like structures. This method is derived using dynamic equation of undamaged/damaged plate, in which local change in flexural rigidity is characterized utilizing a damage distribution function. The SDIM requires to modal data in the intact state and frequency response of damage state where most of vibration based damage identification techniques requires to modal data in both states. Change of mode shapes of damaged plate are approximated as a linear combination of mode shapes of intact plate and are considered in dynamic equation of damaged plate. Constant Coefficients of linear combination have been evaluated using perturbed equation of motion and the damage distribution function. Two strategies for making the inverse problem damage identification are introduced in connection with damage the present SDIM: (1) by using sensitivity of natural frequencies and (2) by using FRF-data, a sufficient number of equations can be derived to detect magnitude and location of damage. The feasibility of presented method is validated through some numerically simulated damage identification test taking into account random noise in FRF-data. Manuscript profile
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      55 - Statistical Evaluation of Induced Seismicity at the Karkheh Dam, Iran
      Seyed Majdedin Mir Mohammad Hosseini Pegah Rajaei
      Karkheh Dam is the largest dam in Iran with a capacity of about 7.4×109 cubic meters and height of 127 meters. Since the first impoundment, increasing in seismic activity in the dam area has been observed that indicates the possible occurrence of reservoir-induced More
      Karkheh Dam is the largest dam in Iran with a capacity of about 7.4×109 cubic meters and height of 127 meters. Since the first impoundment, increasing in seismic activity in the dam area has been observed that indicates the possible occurrence of reservoir-induced seismicity (RIS).In the present work, a preliminary evaluation is conducted firstly in order to investigate these observations. Based on the assessment of the number of earthquakes occurred in equal time periods before and after reservoir impoundment and their focal depths, it is concluded that RIS is happening in the dam site. Secondly, a cross-correlation method is applied in order to find the relationship between water level fluctuations and the variations of seismic activities. This analysis confirms a strong relationship between fluctuation of the water level and the number of seismicity events in the dam area. Manuscript profile
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      56 - The Influence of Pet Fibers on the Properties of Fresh and Hardened Concrete
      N Shamskia
      There is a worldwide interest in using fibers of different types in concrete mixtures. In this regard, as the use of PET fibers has gradually increased during the last decade, this study aims to investigate the effects of PET fibers on the mechanical properties of harde More
      There is a worldwide interest in using fibers of different types in concrete mixtures. In this regard, as the use of PET fibers has gradually increased during the last decade, this study aims to investigate the effects of PET fibers on the mechanical properties of hardened concrete and the workability of fresh concrete. To this end, different contents of PET fibers (PC= %0, %0.5, %1 and %1.5) are added to a concrete mixture and the workability of fresh concrete samples are measured by the slump tests. Furthermore, the load-displacement behavior of the concrete samples is investigated in flexural and compression samples. Results of this study reveal that PET fibers can noticeably change the energy absorption of concrete samples, especially in flexural specimens. Manuscript profile
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      57 - Analysis of the Earth Dams Function against the Effects of Long-Term Deposition in Reservoirs (Polrood Earth Dam-Guilan Province)
      Mahdi keshavarz Nasser Shamskia
      Estimation of sediment transport load due to erosion in river basins is one of the issues which is indispensable for many projects related to water resources, soil and damps construction. With regards to the phenomenon of erosion and transmission Sedimentation in rivers More
      Estimation of sediment transport load due to erosion in river basins is one of the issues which is indispensable for many projects related to water resources, soil and damps construction. With regards to the phenomenon of erosion and transmission Sedimentation in rivers has always led to deformation in the seaboard and sedimentation, so the management and planning in bank of rivers is important in water and soil resources and damp construction. Therefor checking the flow capacity of the sediment transportation and the sediment transportation mechanism in the river hydraulics and their sedimentation in dams are always one of the most fundamental problems in dams construction, and consumable life of dams are also directly related to this phenomenon. To deals with this issue, in this research, after predicting the 57-year-old sediment, the effects of sediment on Polrood earth-filled dam has been investigated by using FLAC3D software, which results show that the effective stress and displacement in the upstream shell is approximately equal to the state without applying sediment pressure. Manuscript profile
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      58 - Effect of Polypropylene Fibers on Strength and Thermal Resistance of Concrete
      Jamal Ahmadi Hossein Aghajanloo
      In this paper, the effect of Polypropylene Fibers added to concrete on strength and thermal resistance of high strength concrete has been investigated. Therefore, five tests have been carried out to reach this goal which it includes; effect of weight percent of polyprop More
      In this paper, the effect of Polypropylene Fibers added to concrete on strength and thermal resistance of high strength concrete has been investigated. Therefore, five tests have been carried out to reach this goal which it includes; effect of weight percent of polypropylene fibers on mechanical properties of concrete, effect of fiber’s length on the strength of high strength concrete, effect of fiber’s volume on the thermal stability of high strength concrete, examine the phenomenon of spalling concrete high resistance against heating, determine the changing of compressive strength of high strength concrete in different temperatures. The results present that the compressive strength has declined with the percentage of fiber concrete after 0.7 kg/m3 . Moreover, in all cases the tensile strength and concrete’s bending strength will be increased by fiber content. Manuscript profile
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      59 - Comparison of Geotextile Layers Effects on Static and Dynamic behavior of Pavement
      Reza Nazari Rouzbeh Dabiri
      One of the methods for the improvement of soil against the tensile stresses is using the artificial supplements in soil such as metal belts or nets, polymer materials and natural fibers. Technically this method is called the reinforced of soil. When a pavement is locate More
      One of the methods for the improvement of soil against the tensile stresses is using the artificial supplements in soil such as metal belts or nets, polymer materials and natural fibers. Technically this method is called the reinforced of soil. When a pavement is located on soft soil, great deformations can occur as a result of the crossing of traffic load in superstructure layers of the body. This can finally lead to the increase in the cost of maintenance and traffic pause in transportation. The main purpose of this study is to explore the effect of geotextile layers place in various depths of the body of pavement layers located on soft soil. For this purpose, models with the identical geometry from the transection of road using Finite Element Method software, PLAXIS were analyzed in two dimensions in which the location and the number of geotextile layers were considered in various depths. In continue, these models have been under static and dynamic loadings due to vehicles and the settlement rate and the lateral deformation of pavement in section has been evaluated. The results show that in static loading, the maximum safety factor of stability is that of layers in which the geotextile exists in the partition between subgrade and embankment layers. Also, between dynamic loading and increasing number of geotextile layers favorable result is not achieved. Although more studies need to be carried out in this area. Manuscript profile
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      60 - World Experiences of Inter-basin Water Transfer Projects and the Necessity of Developing Decision Making Criteria in Iran
      Abbas ali Tayefi Nasrabadi Atefeh Dehghan Touranposhti
      When categorizing water management alternatives, to meet water needs, water transfer is seen as an option that tends to supply more water. Most developing countries where limited water resources are available with high spatiotemporal dispersion, favor this option. The n More
      When categorizing water management alternatives, to meet water needs, water transfer is seen as an option that tends to supply more water. Most developing countries where limited water resources are available with high spatiotemporal dispersion, favor this option. The numbers of such projects that have been proposed, implemented, and operated in recent years evidence the desirability of this alternative. World experiences of inter-basin water transfer however prove that having holistic, systemic view, along with taking into account the principles of sustainable development as well as lifetime cost-income balance are required for such projects to be implemented. This paper intends to put emphasis on the fact that when water transfer projects are being examined, the principle of transparency and public acceptance should be recognized. In doing so, the world experiences and criteria are demonstrated and Beheshtabad project is briefly described. Moreover, it argues that it is not logical to regard the long term average yield as a basis for estimating the water availability at the source basin. The benefits of the project should be fairly distributed between source and destination basins and it is required to thoroughly investigate the other alternatives along with water transfer option. Manuscript profile
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      61 - Numerical Investigation of Subgrade Reaction Coefficient in Sand Soils of Bandar Abbas City
      Adel Asakereh Masood Mossafa
      The soil-foundation interaction is one of the most important issues in geotechnical engineering that deals with studying the soil behavior subjected to the side loading. Winkler’s model is the first and simplest method for consideration of the soil-foundation inte More
      The soil-foundation interaction is one of the most important issues in geotechnical engineering that deals with studying the soil behavior subjected to the side loading. Winkler’s model is the first and simplest method for consideration of the soil-foundation interaction. It is vitally important to determine the coefficient of subgrade reaction of the soil. Since several methods have been provided to estimate the coefficient of subgrade reaction up to now, this research is conducted to choose a ground characteristic in Bandar Abbas (IRAN). To do so, the obtained results from the proposed experimental formulas are compared with corresponding values of the behavioral models to determine the coefficient of subgrade reaction. In addition finite element analysis is performed using Plaxis software. The result of this paper shows that the finite element method is more compatible than Biot's method. Results also showed an increasing footing diameter which leads to the decrease of the Ks. This fact is because of an increasing load area which concluded to the increasing of the settlement. It is found that with increasing each of the strength parameters of the soil ( ) can be expected an effect on increasing the subgrade reaction; although this increase depends on footing diameter. Also, in sand soils, the cohesion of the soil is more effective on the increase of the subgrade reaction coefficient than the internal friction angle. Manuscript profile
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      62 - The Behavior of Suction Bucket under Cyclic Loading in Saturated Lands
      Seyed.Majdedin Mir Mohammad Hosseini M. Emdadi Far T.S. Mir Mohammad Hosseini
      Numerical modeling was carried out to investigate the responses of suction bucket foundations under vertical cyclic loading. Numerical results were compared with centrifuge experiment results. Before the capacity of the model suction bucket to resist cyclic loading coul More
      Numerical modeling was carried out to investigate the responses of suction bucket foundations under vertical cyclic loading. Numerical results were compared with centrifuge experiment results. Before the capacity of the model suction bucket to resist cyclic loading could be investigated, the static pullout capacities had to be determined. The buckets with different aspect ratio are investigated under static and cyclic loading. In the constant diameter by increasing aspect ratio the cyclic bearing capacity will be increased and the slope of graph (cyclic bearing capacity versus aspect ratio) becomes greater by increasing diameter. Under cyclic loading, the uplift capacity of the bucket was found to be 60–76% of the monotonic capacity. It is shown that when the loading amplitude is over a critical value, the sand at the upper part around the bucket is softened. Large settlements of the bucket and the sand layer around the bucket are induced by cyclic loading. Manuscript profile
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      63 - Post-Tensioned Steel Connections Self-Centering Behavior Using the Finite Element Method
      Mahmoudreza Shiravand Ahmadreza Torabipour
      Due to lack of the proper and well behavior of steel moment-resisting connections subjected to the great and major earthquakes, excessive researches have been conducted to mitigate the damages on the primary elements and connections. Therefore, elimination of residual d More
      Due to lack of the proper and well behavior of steel moment-resisting connections subjected to the great and major earthquakes, excessive researches have been conducted to mitigate the damages on the primary elements and connections. Therefore, elimination of residual drift and increasing the plastic rotation capacity for the connectors in the panel zone are required. The main purpose of this study is to numerically investigate the behavior of the recent kind of the steel moment connections which are called as steel self-centering post-tensioned connections. The steel post-tensioned connections consisted of some high strength strands for self-centering feature plus energy dissipater angles for adjustment of plastic deformation. This paper studies on the steel self-centering post-tensioned connections using the finite element method. The obtained results are verified based on the experimental study. Accordingly, the energy dissipation, rigidity percentage, and ductility factor of the connections are determined. Results revealed the perfect self-centering with the proper ductility factor. Furthermore, it was observed that the post-tensioned steel connections have a high plastic rotation capacity without any damages to the column and beam. Manuscript profile
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      64 - Deep Excavation Hazard Assessment Zoning in District 1 in Shiraz Municipality Using Geographic Information System (GIS)
      Sara Afarid Alireza Hajiani Boushehrian
      This research presents the geotechnical zoning map of district 1 in Shiraz municipality with focus on municipal deep excavation hazard assessment on data from 160 boreholes. For this purpose, the mechanical properties are determined according to the results of direct sh More
      This research presents the geotechnical zoning map of district 1 in Shiraz municipality with focus on municipal deep excavation hazard assessment on data from 160 boreholes. For this purpose, the mechanical properties are determined according to the results of direct shear, uniaxial, and SPT tests and then excavation hazard assessment with depths of 3, 6 and 9 m, in situations where the excavation depth of the neighbor foundation is below 0 and 0 to 20 meters have been calculated. Finally, using ArcGIS software, the assessment hazard excavation for 6 different modes was zoned and the zoning map of the assessment hazard excavation with the normal, high and very high hazard index is provided. The zoning maps shows that with increasing depth of excavation, the danger is increased, so that in maps whit depth of excavation of 9 meters, more than 90 percent of points have high hazard index. Manuscript profile
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      65 - Evaluation of Nonlinear Dynamic Response of Rigid and Semi-Rigid Steel Frames under Far-Field Earthquake Records
      Fariborz Farhadi Ali Anvarsamarin
      The purpose of this research was to evaluate the nonlinear dynamic response of rigid and semi-rigid steel frames under Far-Fault Earthquake Records. Accordingly, the fragility curve of the moment frames with rigid and semi-rigid connections was determined. Considering t More
      The purpose of this research was to evaluate the nonlinear dynamic response of rigid and semi-rigid steel frames under Far-Fault Earthquake Records. Accordingly, the fragility curve of the moment frames with rigid and semi-rigid connections was determined. Considering the analytical knowledge of structures in the past, the analysis and design of steel frames based on the assumptions of rigid or joint connections. While laboratory studies show that most connections are semi-rigid and due to the importance of connections in the structures, it is very important to recognize and accurately study their behavior, especially during an earthquake, and their design must be under their real structural behavior. For this purpose, three two-dimensional steel moment frame structures with 6, 12, and 18 stories were used, which represent short, medium, and high structures. Considering the rigid and semi-rigid connections, their seismic performance was investigated using the nonlinear dynamic incremental analysis (IDA). Three cases of connections have been selected corresponding to 50, 60, and 70% rigidity. Finally, the collapse fragility curve parameters obtained and compared. According to the obtained results, decreasing the rigidity of the beam-to-column connections increases the dispersion of the collapse fragility curve. Besides, it was observed that considering the semi-rigid connections leads to a reduction of the median of the collapse fragility curve. The result shows that the mentioned difference cannot be neglected. Manuscript profile
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      66 - EffectofMetakaolin and Nano-SiO2onshort and Long-term shrinkageofself-compactingcement sandmortar
      Hassan Soltanshahi
      The use of cementitious products isincreasing in the world,Thusreplacement part of cement with pozzolanic materials reduced energy consumption and preserve natural resources and the environment and also improve the mechanical properties and durability of the cement mort More
      The use of cementitious products isincreasing in the world,Thusreplacement part of cement with pozzolanic materials reduced energy consumption and preserve natural resources and the environment and also improve the mechanical properties and durability of the cement mortar.Furthermore Nano technology has promptedto tremendous developments in technology of building materials in recent yearsso use of nano-silica has considered by many researchers.On the other hand the use of self-compacting mortar due to high performance and flow ability has increased remarkable in recent years. One of the major issues affecting on durability of cement products is shrinkage of cement mortar.Because of the importance of self-compacting mortar and role of additives pozzolanic, particularly at the nanoscale, in this laboratory study the binary blend of Metakaolinpozzolan and Nano-SiO2as replacement part of the cement have been used. The rate of shrinkage of self-compacting mortar has been investigated.Therefore Metakaolin with percent by weight 10, 15 and 20 and Nano-SiO2with percent by weight 1% and 2% were replaced cement. The results show that using metakaolin,Nano-SiO2 and combination of them reduce the rate of shrinkage of self-compacting cement mortar. Manuscript profile
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      67 - The effect of discrete lateral and torsional bracings stiffness on the elastic lateral-torsional buckling of mono-symmetric I beam, under the concentrated moment
      E. Mohammadi J. Asgari Marnani S. Tavousi M.S. Rohanimanesh
      When the out-of-plane stiffness of a beam is remarkably lower than the in-plane stiffness, the lateral-torsional buckling occurs. In this study, the behavior of mono-symmetric I-beams with discrete torsional and lateral bracings under the concentrated moment is investig More
      When the out-of-plane stiffness of a beam is remarkably lower than the in-plane stiffness, the lateral-torsional buckling occurs. In this study, the behavior of mono-symmetric I-beams with discrete torsional and lateral bracings under the concentrated moment is investigated using the finite element analyses. Then, based on the numerical analyses, equation for the stiffness requirement is proposed. The results show that the location and the type of the bracing have an important role on the stiffness requirement and buckling strength. Manuscript profile
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      68 - Implementing IWRM in IranRecommendations Based on Global Experiences
      Abbasali Tayefi Nasrabadi Atefeh Dehghan Touranposhti
      IWRM is an empirical concept which has been founded on the experience of water practitioners. In other words, it is not a scientific theory to be confirmed or rejected. In turn, it is a set of guidelines derived from conventional understanding of key elements of water m More
      IWRM is an empirical concept which has been founded on the experience of water practitioners. In other words, it is not a scientific theory to be confirmed or rejected. In turn, it is a set of guidelines derived from conventional understanding of key elements of water management. Experience shows that the countries and governments who start reforms in water sector, focus on policy making, and law/regulation developing in the first place. Some challenges of IWRM implementation pertain to the integrity and the extent on the integrity. Ideally speaking, the implementation of IWRM required the integration of all aspects. In order to achieve this, coordination is the first step. IWRM implementation might take several decades to reach the point at which one can claim the water resources management is being done in accordance with principles. The pace of IWRM implementation is developing countries is slow since these countries have poor institutional capacity for change. IWRM implementation requires balancing the conflicting objectives. Having stakeholders involved is also crucial for carrying out the IWRM approach and its effectiveness. Active, non-governmental organizations or any other civic bodies are also required for the negotiations between inter-sector and stakeholders at various levels, to take place. Manuscript profile
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      69 - Earth Pressure behind an Integral Bridge Abutment and Comparison with that behind a Conventional Bridge Abutment under Traffic Loads
      Fatemeh khatibi Seyed Majddin Mir Mohammad Hosseini
      Integral bridges are gaining increased popularity because of both economic and fast construction associated with the omission of bearing supports and expansion joints. In the present study the cyclic earth pressure behind integral bridge abutments under traffic surcharg More
      Integral bridges are gaining increased popularity because of both economic and fast construction associated with the omission of bearing supports and expansion joints. In the present study the cyclic earth pressure behind integral bridge abutments under traffic surcharges are investigated and compared with that induced behind the abutment of conventional bridges (with isolated deck and abutment) under the same surcharges. A numerical modeling has been developed to evaluate the dynamic earth pressure using the FLAC package. The model was calibrated by direct measurement of earth pressure behind a physical model developed in soil mechanics laboratory to study the behavior of retaining walls.The induced earth pressures under static and cyclic conditions are evaluated and the pressure distribution behind the wall as well as the point of application of the total thrust was determined. The results have shown significant changes happen in both quantity and distribution of earth pressure behind the abutment when using integral bridges. The details of findings and their causes will be discussed in the next sections. Manuscript profile
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      70 - An Investigation on the Behavior of Retaining Structure of Excavation Wall Using Obtained Result from Numerical Modeling and Monitoring Approach. (A Case Study of International "Narges Razavi 2 Hotel", Mashhad)
      Soheil Ghareh Mehdi Saidi
      With the growing population and density in metropolitan areas, higher tendency to live in high-rise buildings, and increasing demand for parking lots, it seems necessary to excavate soil to construct underground spaces. During excavation work, as the height of the wall More
      With the growing population and density in metropolitan areas, higher tendency to live in high-rise buildings, and increasing demand for parking lots, it seems necessary to excavate soil to construct underground spaces. During excavation work, as the height of the wall increases, special care should be taken to the wall stabilization to avoid any consequent damage including extensive property damage or loss of life. Different methods such as performing steel or concrete pile, sheet piling, reciprocal anchorage, diaphragm wall, soil nailing, and soil anchorage can be utilized to stabilize excavation wall. As all of these methods have their own advantages and disadvantages, it is important to know the limitations and differences of each method. Besides providing more work space in the wall, using novel methods of stabilization may lead to considerable savings in cost and time. By examining the behavior of retaining structure and also predicting the value of wall displacement, resulting from existing loads such as adjacent structures of the wall, service loads, and vehicle live load, a big step can be taken to prevent any probable damage. Currently, due to the development of high speed digital computers, finite element method (FEM) can be applied to predict the behavior of retaining structure. In this paper, as a case study, the behavior of retaining structure of excavation wall of Narges Razavi 2 International Hotel, Mashhad, stabilized using steel pile and soil anchorage, has been investigated. For this purpose, the results obtained from finite difference software, FLAC2D, and finite element software, PLAXIS2D, have been compared with those obtained from the monitoring of excavation wall. It was found that there is a good consistency between the results. Manuscript profile
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      71 - Effects of Building Construction Overburden on Liquefaction Potential of Soils
      Reza Sallakh Niknejad Sallakh Niknejad Rouzbeh Dabiri
      As one of the significant phenomena in earthquake geotechnical engineering, liquefaction can cause severe damages. A number of factors play a role in the occurrence of liquefaction such as magnitude of earthquake, void ratio, relative density, and fines content percenta More
      As one of the significant phenomena in earthquake geotechnical engineering, liquefaction can cause severe damages. A number of factors play a role in the occurrence of liquefaction such as magnitude of earthquake, void ratio, relative density, and fines content percentage. The impact of building construction overburdens on liquefaction is of paramount importance. The present study was aimed at evaluating the effects of overburden resulting from building construction on liquefaction potential of saturating soil layers along Tabriz Metro Line 2. Fifty-four boreholes and geotechnical information were collected from the research site. Overburden values were considered to be 100 kPa, 200kPa, 300 KPa, and 400 KPa equivalents to 5-, 10-, 15-, and 30-story building, respectively. The assessment of liquefaction potential of soil layers was carried out using the standard penetration test (SPT) method. Furthermore, liquefaction potential index (LPI) of soil layers was evaluated. The findings demonstrated that overburden can affect liquefaction resistance of soil layers. With increasing overburden, safety factor against liquefaction became less than one in nearly 80% of soil layers. The rate of growth in LPI of boreholes in the research site was found to be roughly 70%. Hence, an increase in overburden elevated liquefaction hazards in the research site. Manuscript profile
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      72 - Buckling of Stiffened Thin Walled Cylindrical Shells due to Global Shear
      Mehran seyedRazzaghi F. Karimi
      Thin walled cylindrical shells are important components of industrial structures such as liquid storage tanks, silos, etc. Shell buckling is usually a major failure mode of thin walled shells under extreme loads such as earthquakes. Longitudinal and radial stiffeners ar More
      Thin walled cylindrical shells are important components of industrial structures such as liquid storage tanks, silos, etc. Shell buckling is usually a major failure mode of thin walled shells under extreme loads such as earthquakes. Longitudinal and radial stiffeners are generally used in order to increase buckling capacity of thin walled shells. During an earthquake, cylindrical shells may experience global shear and suffer shear buckling. Buckling of thin walled shells is highly dependent to imperfections. In this study buckling of imperfect cylindrical stiffened tanks due to global shear and seismic loads are studied. To this end nonlinear FE static analyses have been performed in order to estimate buckling capacity of imperfect cylindrical stiffened tanks due to global shear. Herein cylindrical tanks of a constant height and different height to diameter (H/D) ratios were considered. Different arrangements of stiffeners were considered for each tank. Random patterns of imperfection with moderate imperfection amplitude were considered in all tanks. Design relations have been presented based on the results of numerical analyses. Finally, time history analyses were performed in order to evaluate the validity of suggested design relations for buckling of cylindrical stiffened tanks due to seismic loads. Manuscript profile
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      73 - Buckling of Stiffened Thin-Walled Cylindrical Shells under Axial Compression with Symmetrical Imperfections
      Armin A.NobakhtNamin
      This study aimed to investigate the effects of stiffeners on buckling of thin cylindrical shells under uniform axial compression. To this end, more than 300 finite element models of stiffened cylindrical shells were prepared. The variables considered are shell thickness More
      This study aimed to investigate the effects of stiffeners on buckling of thin cylindrical shells under uniform axial compression. To this end, more than 300 finite element models of stiffened cylindrical shells were prepared. The variables considered are shell thickness, number, dimension and the location of the vertical and horizontal stiffeners as well as circular symmetrical imperfections. Results show that the stiffeners can increase buckling of the stiffened cylindrical shells under axial compression. It is also shown that buckling of the cylindrical shells is susceptible to some circular imperfection patterns. In this context, buckling graph of the models are compared with each other; obviously, the stiffened shells with more stiffeners have upper buckling graph in force - displacement curves. Manuscript profile
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      74 - The New Generation of Concrete with the Approach of Ductility: Review
      Javad Chegini
      The present study examines the new generation of concrete. Concrete has long been a major problem, is its ductility. Traditionally, remembering the words of concrete, compressive strength also comes to mind. Compressive strength is not only parameter of necessary and su More
      The present study examines the new generation of concrete. Concrete has long been a major problem, is its ductility. Traditionally, remembering the words of concrete, compressive strength also comes to mind. Compressive strength is not only parameter of necessary and sufficient for a material. Concrete is basically brittle material. By adding the steel in this material is an attempt to ductile it. Provide the necessary ductility, with the addition of the steel and high costs is possible. Is it possible to concrete without adding the steel to the desired ductility that desire? In the future, the studies in this regard will be discussed. Manuscript profile
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      75 - Free Vibration Analysis of Repetitive Structures using Decomposition, and Divide-Conquer Methods
      L Shahryari
      This paper consists of three sections. In the first section an efficient method is used for decomposition of the canonical matrices associated with repetitive structures. to this end, cylindrical coordinate system, as well as a special numbering scheme were employed. In More
      This paper consists of three sections. In the first section an efficient method is used for decomposition of the canonical matrices associated with repetitive structures. to this end, cylindrical coordinate system, as well as a special numbering scheme were employed. In the second section, divide and conquer method have been used for eigensolution of these structures, where the matrices are in the block tri-diagonal form. In the third section a comparison of the results is presented. In order to illustrate the efficiency of the aforementioned methods, repetitive structures are considered in the form of barrel vault space structures. Manuscript profile
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      76 - Numerical Analysis of Cyclic Behavior of Beam-To-Column Bolted Connections in Steel Frames
      Morteza Rastian Asghar Vatani Oskouieb Hassan Aghabaratic
      This article considers the seismic behavior of beam-to-column joints in steel frames for different bolt arrangements by using of finite element modeling. As the most important beam-to-column joint type, the beam-to-column joints with end-plate is chosen for the analysis More
      This article considers the seismic behavior of beam-to-column joints in steel frames for different bolt arrangements by using of finite element modeling. As the most important beam-to-column joint type, the beam-to-column joints with end-plate is chosen for the analysis. Four different specimens have been analyzed. These models had some differences such as bolt arrangement and the presence or absence of end-plate stiffeners. Design of bolts arrangement and stiffeners have been done based on the AISC standards. Two vertical bolt arrangements, with or without stiffener and two other models with horizontal bolt arrangement, with or without stiffeners have been considered. Different aspects such as energy absorption, ductility, initial stiffness and effective stiffness for all specimens have been compared. Finally effect of pre-stressing of all specimens has been assessed. As a result, comparison between vertical bolt arrangement and horizontal bolt arrangement has shown that the vertical bolt arrangement is more advantageous, especially in energy absorption Manuscript profile
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      77 - Investigation of Stress-Strain Behavior of Plastic Concrete Using Monotonic Triaxial Compression Tests
      y. Pashang pisheh seyed majddin Mir mohammad hosseinib
      In this paper, the mechanical behavior of plastic concrete being used in the cut-off walls of earth dams has been studied. To do the task, triaxial compression tests on the specimens in various ages and mix designs under different confining pressures have been done and More
      In this paper, the mechanical behavior of plastic concrete being used in the cut-off walls of earth dams has been studied. To do the task, triaxial compression tests on the specimens in various ages and mix designs under different confining pressures have been done and the stress-strain behavior of such materials and their strength parameter changes has been experimentally investigated. It has been observed that increasing the confining pressures applied on the specimens causes the material behavior to be alike the more ductile materials and the compressive strength increases considerably as well. Moreover, a parametric study has been carried out to investigate the influence of essential parameters affecting the shear strength parameters of these materials. According to the research, increasing the coarse to fine aggregates ratio leads to the increase of compressive strength of the specimens as well as the increase of the cohesion and internal friction angle of the materials. Furthermore, the bentonite content decrease and the cement factor increase results in an increase of the cohesion parameter of plastic concretes and decrease of the internal friction angle of such materials. Manuscript profile
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      78 - Comparison of plasticity and stiffness of steel shear walls with composite steel plate shear wall
      Leila Shahryari Mahdi Esfandiari
      The steel shear wall and composite steel plate shear wall is introduced in recent three decade and is considered and is spread rapidly. Composite steel plate shear wall which is made of a layer of thin steel sheet with coating of reinforced concrete in one or both sides More
      The steel shear wall and composite steel plate shear wall is introduced in recent three decade and is considered and is spread rapidly. Composite steel plate shear wall which is made of a layer of thin steel sheet with coating of reinforced concrete in one or both sides of steel palate is considered a third generation of resistance shear walls against lateral loads that in addition to increasing the strength, ductility and energy absorption, it is very economical and affordable and it is used in constructing high buildings, retrofitting buildings and tanks. In this paper we have tried to examine the seismic behavior of steel and composite shear walls. For this purpose several models of steel shear and composite walls from one to five stories were constructed and analyzed by Abaqus software. The result show that composite steel plate shear walls has more ability to absorb energy, spread produced stress to different parts of the steel plate and ductile than steel shear walls. The curve hysteresis loop of composite steel palate shear walls is more stable and sustainable than steel shear wall. With increasing the number of stories, the initial strength and stiffness is decreased due to increase in lateral shift but the amount of absorbing energy and ductility is increased. The force tolerance in composite steel plate shear wall models is increased in comparison with steel shear walls Manuscript profile
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      79 - Experimental Study on the Effect of Crumb Rubber on Shear Strength of Sandy Soil
      Soheil Ghareh Seyed Vahid Mojtahed Sistani
      Nowadays, soil reinforcement using polymer elements have been investigated by a number of researchers in order to increase the load capacity of soils. Reinforcing soils using fibers is a method of soil improvement, which offers a homogenous mixture in combination with s More
      Nowadays, soil reinforcement using polymer elements have been investigated by a number of researchers in order to increase the load capacity of soils. Reinforcing soils using fibers is a method of soil improvement, which offers a homogenous mixture in combination with soils, regarding their tensile strength. This combination maintains pressure loading capacity and properties in mutual resistant tensile. The present research investigates the effect of crumb rubber bearing the size of 5mm × 5mm and 10%, 25% and 40% volume on sandy soil behavior using large-scale direct shear test (300mm × 300mm × 150mm) under the vertical stresses of 50, 100 and 150kPa. Results showed that the optimum volume percentage of crumb rubber for maximum shear strength is between 20% and 25%. Manuscript profile
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      80 - The Effect of p-delta 21-Storey Structure in the Variable Arrangement of Lateral Stiffness
      Javad Chegini
      In recent years, high-rise construction has been rising. A big challenge for engineers and executives in the construction of these structures is the stability of the structures against earthquakes. And this requires the development of appropriate arrangements for struct More
      In recent years, high-rise construction has been rising. A big challenge for engineers and executives in the construction of these structures is the stability of the structures against earthquakes. And this requires the development of appropriate arrangements for structures under lateral system and are braced system. And this requires the development of appropriate arrangements for structures under lateral system and are braced system. Hence, we decided to evaluate the geometry and arrangement of lateral system for 21-storey of steel structures in two main types do. Also the two groups design 6 model geometry lateral bracing system and mega bracings, with and without consideration of P-delta effect for each of the models we will see this, What role will this effect essentially on the response of structures. And in the end, will have an interpretation of the results. Manuscript profile
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      81 - A Comparative Study on the Seismic Displacements of the Karkhe Large Embankment Dam with Mixed and Pure Clay Core-Iran
      R. Bahrami Seyed Majdedin Mir Mohammad Hosseini M. Asadolahi Pajouh
      The water supply is the crucial problem of human beings in the world. Earth dams are usually the most important structures to store and manage the main sources: surface waters. The safety of earth dams in different conditions especially under earthquake loadings plays a More
      The water supply is the crucial problem of human beings in the world. Earth dams are usually the most important structures to store and manage the main sources: surface waters. The safety of earth dams in different conditions especially under earthquake loadings plays a vital role in sustainable developments. Recently, mixed-clay soil is widely used as water- seal material in the core of earth dams, while limited studies on their seismic behaviors have been carried out so far. This paper discusses about the displacement performance of the Karkhe Large Embankment Dam with mixed- clay core , recently constructed in south-western part of Iran , under earthquake motions and compares the dynamic analyses’ results with those of pure-clay core. In this study, the Karkhe Dam with both mixed and pure clay core is numerically modeled using the FLAC 4.0 software. After calibrating the model and completing the static and dynamic analyses under proper strong motions, selected based on the previous seismological studies, the results, including the maximum settlements, horizontal displacements of upstream and downstream shells under different excitations are compared and discussed. Based on the obtained results, it is noted that the dynamic performance of earth dams with mixed-clay core is more desirable than that of pure-clay core. It is also observed that the seismic settlements of the dam with pure-clay core averagely show an increase of 20 percents compared with that having the mixed-clay core. Manuscript profile
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      82 - The Analysis and Assessment of Executive Methods of Soil Improvement, Based on Sustainability Indexes
      Behnam Radpour naser Shamskia Somaye Daee Mihammad ali Nekoee
      Developing measure performance, especially in civil activities, is mainly based on economic or social approaches, regardless of its environmental effects. This matter has caused imbalances of human life and hazardous future for him. Modern human’s awareness of the More
      Developing measure performance, especially in civil activities, is mainly based on economic or social approaches, regardless of its environmental effects. This matter has caused imbalances of human life and hazardous future for him. Modern human’s awareness of the imbalances in normal performance of the nature cycle, caused by technology, has led him to create some ideas such as sustainability and to consider its components in recent technology. This paper is to take the most appropriate soil improving and enhancing method out of the well-known ones, based on the sustainability framework (society, economy and environment). The methodology is descriptive-analytical. The data or questionnaire sheets were collected and the analysis hierarchical process (AHP) was used in order to achieve optimal analysis and determination of the best choice. The results showed that the soil stabling method is the most appropriate one among the existing methods of soil improvement and that it tends to show the most correspondence with sustainability principles. Regarding the results of this paper, all contractors and those who are involved in construction would be capable of choosing appropriate methods of increasing soil compaction and improving foundation loading, based on the sustainability indexes, which consequently causes remarkable decrease of the environmental damages for present and future generation. Manuscript profile
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      83 - Investigating properties of fresh and hardened self-compacting concrete made of recycled aggregates
      Pouria Javadi Ali Delnavaz
      Self-compacting concrete is a new high performance concrete with high ductility and segregation resistance. In recent years, construction material manufacturers have focused their attention on lightweight concrete and have strived to use lightweight concrete, if possibl More
      Self-compacting concrete is a new high performance concrete with high ductility and segregation resistance. In recent years, construction material manufacturers have focused their attention on lightweight concrete and have strived to use lightweight concrete, if possible, in load-bearing parts of buildings. Concrete with both self-compacting and lightweight properties is favourable in this context which is the so-called lightweight self-consolidating concrete. Given the novelty of self-compacting concrete industry and increased amount of construction materials resulting from earthquake (due to seismic hazards of Iran) and destruction of different buildings, in particular urban decay, on the other hand, feasibility study on production of self-compacting concrete with these materials is justifiable in terms of costs, environment protection and energy conservation. Accordingly, coordination between self-compacting factor and utilising these materials is important. So, in this research, the effect of recycled aggregates on mechanical properties of lightweight self-compacting concrete was investigated. Specimens were analysed using 2 mix designs with different contents (cement) by Slump, J-Ring and compressive strength tests. Results indicated that mix designs containing waste LECA have good consistency and stability. Also, mix designs containing waste scoria have high strength. Hence, in order to achieve self-compacting and lightweight properties, it seems logical to use those two waste materials. Manuscript profile
    • Open Access Article

      84 - A Comparison of Different Non-linear Numerical Models for Pier Shaft Interaction Analysis for study of the Seismic Performance of Bridges
      Shahriar TavousiTafreshi Amin Ghafooripour Seyed shahrum Jafari
      The AASHTO code of practice for design of bridges shows that the ductility level for foundation is given equal to one. Bridges are classified in three classes. For class of essential and normal bridges a question for not to use ductility level due to the importance of b More
      The AASHTO code of practice for design of bridges shows that the ductility level for foundation is given equal to one. Bridges are classified in three classes. For class of essential and normal bridges a question for not to use ductility level due to the importance of bridges’ costs is become an important item in different countries particularly in Middle east. This paper aimed to study on performance of bridges based on the effect of soil non-linear behavior. A comparison between Finite Difference (F.D), Finite Element (F.E) methods and close form solutions has been carried out on single and group piles under lateral loads in multilayered soils. Winkler model with non-linear springs, FLAC-3D, ANSYS5.4 and ABAQUS software were used for verifications. The Lagrangian method was considered in FLAC-3D and the Drucker-Prager was used in ANSYS. Pile behavior in sandy soils, uniform clayey soils, clayey deposits including sandy lenses, and Sand deposits with thin clay layers were analyzed. Verification between traditional close form solution methods with those analysis methods were carried out. Results show the effectiveness of foundation ductility in compare with the expected ductility levels and structural performance for superstructure. The ductility level of substructure due to the pile soil interaction has found equal to 3.5 to 4.5 for different soil types. It show in “Pile and Deck (pier shaft)” model in bridges for the normal and essential bridges classes the use of ductility should be taken into account in accordance with soil-structure performance. In conclusion the paper shows that for the pier shaft system it would be possible to use ductility level for foundations for normal and essential class of bridges and for those countries that they use the structural ductility for design of all components of structure including piles, the level of performance should be precisely investigated and using of structural ductility level is under question for design of pier shaft models. Manuscript profile
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      85 - Seismic behavior of RBS connections at near and far field earthquakes
      Maziar Basirololoomi Armin Aziminejad Fariman Ranjbaran
      Moment-resisting frames have extensive usage in earthquake-prone areas and high ability in energy dissipation.After the earthquake in Northridge 1994,Kobe 1995 fixed connections of steel structures have shown poor performance and generally they were caught brittle fract More
      Moment-resisting frames have extensive usage in earthquake-prone areas and high ability in energy dissipation.After the earthquake in Northridge 1994,Kobe 1995 fixed connections of steel structures have shown poor performance and generally they were caught brittle fracture of beam flange weld to the column.In order to remedy to avoid similar situations in future earthquakes,researchers introduced connection with reduced beam section in name of RBS(Reduced Beam Section),that stress concentration at the junction can be prevented by reducing the local section of beam in the vicinity column and location of plastic hinge transferred from connection to the distance from the column. In this research, firstable the three special steel moment-resisting frames of three-dimension 5,10 and 15 story with seismic compressed sections as RBS was analyzed as time history by using SAP software at the near and far field earthquakes with and without considering the effect of vertical component,then a critical connections in each of the frames was modeled by ANSYS software and it was analyzed as dynamic under obtained loads from each record(in SAP). The study results showed that the vertical component put negative effects on the performance of this type of connection in terms of concentration of stress, strain and ductility.It is necessary to say that the negative effect of the vertical component on the connections at near field earthquakes was comparatively more than at far field earthquakes. Manuscript profile
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      86 - Finite Element Method for Static Cyclic Behavior of Steel Shear Wall with Corrugated Plates
      Mohammad Reza Farhadi Hassan Aghabarati Hadi Niromand Jazi
      The system of steel shear wall is an initiative resistance system against the lateral load such as an earthquake and the wind that has been researched in the last three decades. Currently, this system is noticed more than other systems because of adequate stiffness, duc More
      The system of steel shear wall is an initiative resistance system against the lateral load such as an earthquake and the wind that has been researched in the last three decades. Currently, this system is noticed more than other systems because of adequate stiffness, ductility, and more energy absorption. The system of steel shear wall with corrugated sheets has been offered as an innovative system, since the construction of panels for hard-set steel shear wall is expensive and also it causes the increscent of weight construction. This type of system has been developed using of hard outer plate from geometry of corrugation shape that has better buckling strength than hard-set and flat case in this study. This study is conducted to compare the strength and energy dissipation capacity of three different steel shear walls: unstiffened, trapezoidally vertical corrugated and trapezoidally horizontal corrugated under vibration load of AISC 341-10 instruction with 100mm movement. The results reveal that although the ultimate strength of the unstiffened model is nearly 17% larger compared to that of the corrugated models, energy dissipation capacity of the corrugated models are approximately 52% larger compared to the unstiffened model. Manuscript profile
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      87 - Pillow-Shape Base Isolation System and Its Seismic Behavior
      Ali Tayaran Mahmood Hosseini
      In this paper a new isolating system is introduced for short to mid-rise buildings. In comparison to conventional systems such as LRB and HRB, the proposed system has the advantage of no need to cutting edge technology and has low manufacturing cost. This system is made More
      In this paper a new isolating system is introduced for short to mid-rise buildings. In comparison to conventional systems such as LRB and HRB, the proposed system has the advantage of no need to cutting edge technology and has low manufacturing cost. This system is made up of two orthogonal pairs of pillow-shaped rollers that are located between flat bed and plates. By using this system in two perpendicular directions, building can move in all horizontal directions with respect to its foundation. Due to the pillow shape of the roller, this system has self-centering capability which causes it to return to its original position after the earthquake. The rolling friction force between pillows and their bed creates some damping in the system which prevents it from further oscillation after earthquake excitations diminish. The purpose of this study is to evaluate the proposed isolation system’s performance under different earthquake excitations. First of all general features of the proposed isolators have been introduced followed by the analytical equations of the system. Vertical bearing capacity and the effects of the thickness of pillows has been investigated using ABAQUS software. It has been shown that for a pair of pillows of 58 cm width, 45 cm height and 100 cm length the vertical load bearing capacity of the system is more than 300 tons. The period of system with respect to the height and radius of curvature of the rollers, and seismic response of a building, assumed as a rigid body resting on isolators, has been studied subjected to simultaneous effects of horizontal and vertical excitations. It has been shown that the proposed system can reduce the absolute acceleration in the building around 78% in average, while the building’s maximum displacement is around 1.77 times of the ground in average. Manuscript profile
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      88 - Effects of Using Multilayers of High Resistance AFRP on Loading Capacity of Reinforced Concrete Beams in Comparison with Low Resistance AFRP Considering EBROG Method
      Bamshad Sadjadi Manizani Shahriar Tavousi Tafreshi Abbas Akbarpour Nikghalb
      Externally Bonded Reinforcement on Grooves (EBROG) is a new method that has been introduced to postpone or eliminate debonding of FRP sheets from concrete surface in concrete beams strengthened for flexure and increase loading capacity. For strengthening reinforced conc More
      Externally Bonded Reinforcement on Grooves (EBROG) is a new method that has been introduced to postpone or eliminate debonding of FRP sheets from concrete surface in concrete beams strengthened for flexure and increase loading capacity. For strengthening reinforced conceret beams in strructure, use of different types of FRP like: laminate, AFRP, CFRP, and GFRP. By there is some differences between these kinds related to sensitivity to temperature, shear sterength, The aim of the current study is to examine the efficiency of Externally Bonded Reinforcement on Grooves method on Concrete beams' loading capacity when used under multilayers of high resistance AFRP sheet and comparing it with the results of multilayers of low resistance AFRP. For this purpose , beam specimens with dimension 120*140*1000 mm were modeled in ABAQUS program. According to the analysis, loading capacity is increased when used multilayers of high resistance AFRP instead of using multilayers of low resistance AFRP. Finally, diagram shown that use of multilayers of AFRP has better results than use of one layer of AFRP. Manuscript profile
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      89 - Bending Fatigue Tests and Finite Element Models of Steel Rectangular Hollow Sections [SRHS]
      islam Ezz El-Arab W Gray
      The Welding in cold formed areas is not only an open question for statically loaded sections (brittle fracture) but also for dynamically loaded structures (fatigue resistance). A lot of structures are subjected to dynamic loadings and unfortunately very little informati More
      The Welding in cold formed areas is not only an open question for statically loaded sections (brittle fracture) but also for dynamically loaded structures (fatigue resistance). A lot of structures are subjected to dynamic loadings and unfortunately very little information about the influence of welding in the cold formed areas on fatigue resistance is available. In order to establish the fatigue behavior of welded and non-welded rectangular hollow sections specimens, a large number of 4-point bending tests are performed at the Saud Bin Laden Group SBG with cooperation with Buro Happold UK, Laboratory for Steel. Because these tests are very expensive, and because of the large number of parameters regarding the RHS to be investigated (steel grade, wall thickness, load distribution, boundary conditions), a number of finite element models for these specimens are made. By modeling the specimens with different types of finite elements (shells, solids) and taking into account some types of loading distributions and boundary conditions, the obtained results (stresses, strains, displacements) from a static analysis are compared with those obtained from the real 4-points bending tests. In this way, the obtained conclusions would lead to decrease of the number of the specimens that need to be tested as well as the costs of the project. Furthermore, by using finite element analysis, many factors with direct influence on the fatigue resistance can be considered. Manuscript profile
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      90 - Prediction and evaluation of runoff data in south of Qazvin watershed, using a fuzzy logic technique
      Naser Shamskia S.H. Rahmati
      The important criteria for designing in the most of hydrologic and hydraulic construction projects are based on runoff or peak-flow of water. Mostly, this measure and criterion is calculated or estimated by stochastic data. Another feature of these data that are used in More
      The important criteria for designing in the most of hydrologic and hydraulic construction projects are based on runoff or peak-flow of water. Mostly, this measure and criterion is calculated or estimated by stochastic data. Another feature of these data that are used in watershed hydrological studies is their impreciseness. Therefore, in this study, in order to deal with uncertainty and impreciseness, based on Buckley’s estimation method, a fuzzy logic method of evaluating hydrological measures is developed. The method introduces triangular shape fuzzy numbers for different measures in which both of the uncertainty and impreciseness concepts are considered. Finally, to illustrate the methods more explicitly, the two algorithms are tested on a real case data. Manuscript profile
    • Open Access Article

      91 - Free vibration analysisof soft-core composite-faced sandwich plates using three-dimensional finite element method
      Mohammad Mahdi Kheirikhah Hasan Aghabarati Pooneh Khosravi
      In this paper, natural frequencies of the sandwich plates with soft flexible core and composite face sheets are obtained. Three-Dimensional (3D) finite element method (FEM) is used for constructing and analyzing of the sandwich plates to obtain their natural frequencies More
      In this paper, natural frequencies of the sandwich plates with soft flexible core and composite face sheets are obtained. Three-Dimensional (3D) finite element method (FEM) is used for constructing and analyzing of the sandwich plates to obtain their natural frequencies. Continuity conditions for transverse shear stresses at the interfaces as well as transverse flexibility and transverse normal strain and stress of the core are considered.The effects of plate dimensions such as aspect ratio and thickness ratio are studied. Also, different boundary conditions such as all edges clamped (CCCC), all edges simply supported (SSSS) and combined boundary conditions including (CFCF)are applied to the sandwich plates. Comparison of the present results in special case with those of the accurate plate theories confirms the accuracy of the proposedmodel. Manuscript profile
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      92 - A study on strength and durability of self-compacting concretes made of recycled aggregates
      Moslem Mohammadi Jatani Ali Delnavaz
      Given the development of construction industry and design and implementation of high rise buildings with complex sections and various geometrical forms, the use of self-compacting concretes has received the attention of construction engineers and provided great advantag More
      Given the development of construction industry and design and implementation of high rise buildings with complex sections and various geometrical forms, the use of self-compacting concretes has received the attention of construction engineers and provided great advantages. Due to the increasing air pollution in cities, governments encounter the important issue of repelling the pollutants in which construction industry plays a key role; so that recycled concrete has been suggested to decrease the construction pollutants. Therefore, self-compacting recycled concrete can take advantage of the both types of concrete and enormously benefit the environment by decreasing the use of natural aggregates and preventing from deterioration of natural mines The most important properties of good concrete include its workability, strength and durability. The range of these three properties is determined for the concrete made according to EFNARC, ASTM and BS through fresh concrete tests including slump flow, V-funnel, J-ring, L-box, compressive strength, capillary water absorption and water penetration under pressure and the following results are gained. Increasing the amount of recycled aggregates resulted in reduction of self-compacting concrete criteria like slump, J-ring, etc. which indicated decline of plasticity, workability, passing ability and so on and that might be because of grading variations. Compressive strength was dramatically reduced by increasing the amount of coarse recycled aggregate so that compressive strength of concrete specimens declined by 2-10% as the amount of recycled aggregate rose from 25% to 100%. Increasing the amount of recycled aggregates generally enhanced percentage of capillary water absorption; so that according to the results of tests, water absorption rose by 5-15% in specimens by increasing percentage of recycled aggregates, indicating an increase in permeability and a decrease in durability of concrete. The main propose of this article is to determine the optimum replacing percentage of recycled aggregates to find the best compressive strength and durability of self-compacting concrete. Therefore, different samples with replacing recycled aggregates by 0%, 25%, 50%, 75% and 100%, water to cement ratio of 0.35 and 0.45 and different amount of super- plasticizer were. The result shows that by increasing in the amount of recycled aggregates, the strength of concrete decreases while the permeability of concrete reduces. Manuscript profile
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      93 - Mix Design Selection For Old and New Generation of SuprePlasticizers
      Navid Afshari Seiyed Ali Haj Seiyed Taghia
      Determination the optimal mix design plays an important role in order to gain the maximum characteristic strength. This research was conducted as a case study for Manjil tunnel project located in Qazvin-Rasht highway. For this purpose, 18 concrete mix designs were prepa More
      Determination the optimal mix design plays an important role in order to gain the maximum characteristic strength. This research was conducted as a case study for Manjil tunnel project located in Qazvin-Rasht highway. For this purpose, 18 concrete mix designs were prepared at the study phase of the project with specifications such as conventional water-to-cement ratios of 0.4, 0.5 and 0.6, the use of two generations of new and old conventional superplasticizer in Iran (naphthalene sulphonate and polycarboxylate ether types, respectively) with cement weight percentages of 0.2, 0.4 and 0.6. Superplasticizers are used to increase the fluidity of concrete without adding excess water. The naphthalene sulphonate is a polymeric molecule formed by condensation of naphthalene sulfonic acid and formaldehyde, in which the hydrophilic groups are mainly sulfonic groups. It has been demonstrated that polycarboxylate ether can mitigate plastic shrinkage of matrix because of the reduction of the build-up rate of capillary pressure by polycarboxylate ether. Finally, the optimal water-to-cement ratio and superplasticizer weight percentage were determined. Concrete mix designs with different ages of curing were made (0, 3, 7, 14 and 28 days). Manuscript profile
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      94 - Structural Drift Corresponding to the Critical Excitations
      Mohammad Hosein Soltani Seyed Hooman Ghasemi
      While the existing structures, even recently constructed ones are subjected to the critical earthquakes, the catastrophic devastations are expected to occur. Therefore, at least for several important structures such as power plants, infrastructure, and buildings, there More
      While the existing structures, even recently constructed ones are subjected to the critical earthquakes, the catastrophic devastations are expected to occur. Therefore, at least for several important structures such as power plants, infrastructure, and buildings, there is a need to consider the critical excitation analysis. One of the important criteria in the seismic design of the structures using the criteria in critical excitation is to control the maximum amount of structural displacement. However, the required characteristics of the analysis and design of the structures are generally random variables and have many uncertainties. Therefore, the probability-based analysis should be accomplished to determine the most probable structural responses. The main objective of this research is to investigate the reliability level of buildings subjected to the critical excitations for concerning the steel structures. In due course, the wide range of the SDOF structures is investigated subjected to real ground motions of the critical excitations. Eventually, the reliability index for structures is given in terms were divulged. Manuscript profile
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      95 - Estimation of Water Retention Curve for Unsaturated Fine Soils
      seyed majddin Mir Mohammad Hosseini N. Ganjian Y. Pashang Pisheh
      In order to obtain the soil water retention curve of an unsaturated soil which is defined as the relationship between water content and suction, extensive laboratory tests are essential. These laboratory tests are usually costly and time consuming. Moreover, for most pr More
      In order to obtain the soil water retention curve of an unsaturated soil which is defined as the relationship between water content and suction, extensive laboratory tests are essential. These laboratory tests are usually costly and time consuming. Moreover, for most practical problems, it has been found that approximate unsaturated soil properties are adequate for analysis. Thus, empirical procedures to predict unsaturated soil parameters would be invaluable. The water retention curve can be measured or predicted based on soil index properties. Estimation based on index properties is highly desirable due to its simplicity and low cost. In this paper, the constant parameters of well-known Van-Genuchten and Fredlund-Xing equations based on index properties of fine soils are derived. The comparisons show that the curves predicted by these models are in a good agreement with the experimental results. Manuscript profile
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      96 - Numerical Solution of Seismic Wave Propagation Equationin Uniform Soil on Bed Rock with Weighted Residual Method
      M.H. Jahangir
      To evaluate the earth seismic response due to earthquake effects, ground response analyses are used to predict ground surface motions for development of design response spectra, to compute dynamic stresses and strains for evaluation of liquefaction hazards, and to deter More
      To evaluate the earth seismic response due to earthquake effects, ground response analyses are used to predict ground surface motions for development of design response spectra, to compute dynamic stresses and strains for evaluation of liquefaction hazards, and to determine the earthquake induced forces that can lead to instability of earth and earth-retaining structures. Most of the analytical solutions presented are affected by the defect that the stress-strain relationship must be of rather simple form (linear elastic, with perhaps linear hysteretic damping), and that the soil properties must be homogeneous. Real soils are often composed of several layers of variable properties, and often they exhibit non linear properties. Therefore, a numerical solution may be considered, because this can more easily be generalized to non-linear and non-homogeneous properties. In this paper, a simple numerical solution method is presented, again with damping property. The considerations will be restricted to one-dimensional wave propagation in a linear elastic layer which the equation of motion will be resolved with weighted residual method and the advantages of using this method will be ultimately discussed. Of course, the most important benefit of this element free approach is having a suitable approximated function for wave displacement in height of a soil layer. Manuscript profile
    • Open Access Article

      97 - Trial Chemical Grouting in Filter Materials at the Karkheh Dam Site, Iran
      M Heidarzadeh A. A. Mirghasemi Seyed. Majdedin Mir Mohammad Hosseini F. Eslamian
      A sodium silicate-based chemical grout was used in the Karkheh dam site in order to examine the performance of the chemical grouting technique for stabilization of the dam's filter material. Karkheh, an embankment dam with the reservoir capacity of about 7.4 billion cub More
      A sodium silicate-based chemical grout was used in the Karkheh dam site in order to examine the performance of the chemical grouting technique for stabilization of the dam's filter material. Karkheh, an embankment dam with the reservoir capacity of about 7.4 billion cubic meter at the maximum water level, is the largest dam in Iran. The grouting works performed at the dam site, were part of the prerequisites for development of the dam's complementary cut-off wall. Since the dam was completed, the execution of the new cut-off wall from the dam crest was inevitable. Hence, one of the main difficulties associated with the development of the new wall was trenching and execution of plastic concrete wall through filter materials of the dam body. To resolve this technical problem, the method of chemical grouting was employed. However, the process was so challenging since little research work has been devoted to the application of grouting technique in filter. Wide testing program including full scale tests were performed to obtain optimized mix design and grouting program. A full scale platform consisting actual filter materials was constructed and undergone various tests. Results of the testing program revealed that a chemical grout consisting of sodium silicate, water, and ethyl acetate with proper mix ratio can successfully stabilize the filter of the dam body. Manuscript profile
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      98 - Evaluating the Liquefaction Potential of Soil in the South and Southeast of Tehran based on the Shear Wave Velocity through Empirical Relationships
      M Khalili Noutash R Dabiri M Hajialilue Bonab
      The liquefaction resistance of soil can be evaluated using laboratory tests such as cyclic simple shear, cyclic triaxial, cyclic torsional shear as well as field methods like Standard Penetration Test (SPT), Cone Penetration Test (CPT) and Shear Wave Velocity (Vs). In t More
      The liquefaction resistance of soil can be evaluated using laboratory tests such as cyclic simple shear, cyclic triaxial, cyclic torsional shear as well as field methods like Standard Penetration Test (SPT), Cone Penetration Test (CPT) and Shear Wave Velocity (Vs). In this regard, this study attempts to compare the results of the SPT based on the simplified procedure proposed by Seed and Idriss (1985) and those of the Vs on the basis of Andrus et al.’s (2004) process using empirical relationships between them. Iwasaki’s (1982) method is used to measure the liquefaction potential index for both of them. The study area is a part of the south and southeast of Tehran. It is observed that there is not a perfect agreement between the results of the two methods based on five empirical relationships assuming cemented and non-cemented condition for soils. Moreover, the liquefaction potential index (PL) value in the SPT method is more than that of the Vs method. Manuscript profile
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      99 - Influence of Nano-Particles on Characteristics of MetakaolinContained Cement Paste
      Mehran Seyed. Razzaghi A. Shekari J. Poursharifi M. Rajabi
      The influences of nano-ZrO2 (NZ), nano-TiO2 (NT), nano-Fe2O3 (NF) and nano-Al2O3 (NA) additions on properties of the fresh and hardened cement paste in comparison with the fine cement paste were experimentally studied. Mini slump and flow cone tests were conducted on fr More
      The influences of nano-ZrO2 (NZ), nano-TiO2 (NT), nano-Fe2O3 (NF) and nano-Al2O3 (NA) additions on properties of the fresh and hardened cement paste in comparison with the fine cement paste were experimentally studied. Mini slump and flow cone tests were conducted on fresh cement pastes. Moreover the compressive and tensile strength of hardened cement paste were measured. SEM micrographs and XRD powder patterns of hardened cement paste were analyzed in order to evaluate the effects of Nano additives on the microstructure of cement pastes. The results of this study showed that Nano-particles can improve the compressive strength of cement paste. While NA has the most influence on compressive and tensile strength of the cement paste, NZ has the least effect on the compressive and tensile strength of the hardened cement paste. It was also shown that Nano particles can increase the viscosity of fresh cement paste. The results of this study seem to indicate that the most effective Nano-particle content on mechanical properties of hardened cement paste is about 1.5% to 2% for various kinds of Nano-particles. Manuscript profile
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      100 - Evaluation of Effective Parameters on the Underground Tunnel Stability Using BEM
      M Panji J Asgari Marnani Sh Tavousi Tafreshi
      There are various parameters that affect stability and expansion of failure zones in under pressure tunnels. Among the important parameters that affect failure zones around the tunnels are cohesion and internal friction angle of the rock mass. In addition, the cross sec More
      There are various parameters that affect stability and expansion of failure zones in under pressure tunnels. Among the important parameters that affect failure zones around the tunnels are cohesion and internal friction angle of the rock mass. In addition, the cross sectional shape is the considerable point in failure distribution around the tunnels. The stress analysis method is one of the applicable methods for evaluating stability and recognizing failure zones in underground tunnels. On the other hand, numerical stress analysis method, because of obtaining results with simplicity and desirable accuracy, is one of the best methods in stability evaluation of the tunnels. The Boundary Element Method (BEM) has unique advantages in stability analysis of infinite continuums. In this paper, using Hoek-Brown failure criteria and also BEM, failure zones around the tunnels with various section shapes are studied numerically and the effects of cohesion and internal friction angle of rock mass on formation and distribution of failure radii are evaluated. It deserves mentioning that the behavior of the rock mass around the tunnels is assumed to be elastic and the formulations are based on plane strain. Manuscript profile
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      101 - Evaluation of the Effect of Connection between RC Shear Wall and Steel Moment Frame on Seismic Performance and Reduction Factor in Dual Systems
      Ali Molaei Manzar Hassan Aghabarati
      Dual systems of steel moment frame and reinforced concrete shear wall have combined the advantages of steel frames and reinforced concrete shear wall. These walls have increased the lateral stiffness of steel frames and have reduced seismic demands on steel frames thus More
      Dual systems of steel moment frame and reinforced concrete shear wall have combined the advantages of steel frames and reinforced concrete shear wall. These walls have increased the lateral stiffness of steel frames and have reduced seismic demands on steel frames thus providing opportunities to use such system. In this research intermediate dual system of steel moment frame was chosen with intermediate reinforced concrete shear wall in forms of 3, 6 and 9 story structures, similar plan and three manners of burried column in shear wall, non burried column connected to shear wall and non burried column separated frome shear wall using ETABS 2000 software and it was designed according to equivalent static analysis. In order to evaluate effect of connection between RC shear wall and steel moment frame on seismic performance and reduction factor of systems, all structures have been modelled on PERFORM- 3D software and static pushover analysis has done according to the instruction for seismic Existing buildings (360 Iranian code) and FEMA 356. The results of static pushover analysis on structures show that in dual systems of steel moment frame and reinforced concrete shear wall, the model of connection of burried column in shear wall is more regarding its deformability, strength and capacity of energy dissipation and the interaction between frame and wall is also better rather than two types of non burried column in wall. Type of wall connection to frame on reduction factor of dual systems of steel moment frame and RC shear wall has no effect in mentioning structures. Manuscript profile
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      102 - A Study of the Wave Propagation Velocity in Granular Soils Using Discrete Element Method (DEM)
      Mohsen Emdadifard Seyed,Majdedin Mir Mohammad Hosseini
      In the present paper, discrete element method (DEM) is used to study wave propagation phenomenon in granular soils. The effect of factors such as coefficient of friction, frequency, normal stiffness and soil gradation on the wave velocity is studied. Using the wall moti More
      In the present paper, discrete element method (DEM) is used to study wave propagation phenomenon in granular soils. The effect of factors such as coefficient of friction, frequency, normal stiffness and soil gradation on the wave velocity is studied. Using the wall motion based on the sinusoidal function is the method of loading used in this simulation, through which the pressure wave is transferred to particles. Simulations results are well consistent with the results of experiments conducted by other researchers. In addition, the results obtained are shown as graphs to study the effectiveness of each parameter. According to the results, the coefficient of friction and normal stiffness have a greater effect on the wave velocity. Manuscript profile
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      103 - Liquefaction Hazard assessment using Horizontal-to-Vertical Spectral Ratio of Microtremor
      Mehdi Mokhberi Sadegh Yazdanpanah Fard
      In this paper, the spectral ratio of mmicrotremor, HSVR, is presented for estimating the liquefaction potential of layered soil in the coastal area of the Persian Gulf, which consists of a hard sandstone layer situated between two saturated sandy layers. The surface lay More
      In this paper, the spectral ratio of mmicrotremor, HSVR, is presented for estimating the liquefaction potential of layered soil in the coastal area of the Persian Gulf, which consists of a hard sandstone layer situated between two saturated sandy layers. The surface layer is thin, with a thickness between 2 and 5 meters. The purpose of this paper is to identify the relation between the liquefaction potential, the natural frequency and the amplification factor values using microtremors. Liquefaction assessment was done at 27 stations using the HVSR approach provided by Nakamura [1]. HVSR analysis was carried out using the Geopsy software. According to the results of the analysis, the predominant frequency values range from about 0.8 Hz to 2.4 Hz and the amplification factor values range from 1.1 to 2.8. Based on these parameters, the vulnerability index Kg is determined, which can be used as a parameter in calculating the liquefaction potential of an area. The results show that the vulnerability index is related to the sedimentary depth as well as the frequency and amplification factor. Furthermore, the calculated results confirm that the southern area of Bushehr City, which is larger than other areas, has a high liquefaction potential. Furthermore, it is possible to determine the limit of Kg to estimate the liquefaction hazard. Comparing the results confirms that in Bushehr, a soil layer is liquefiable if its related Kg value is over 1.7. This value may change with the conditions of the layer and the soil specification. Manuscript profile
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      104 - Analyzing seismicity hazard in Boinzahra, Qazvin and Hamedan zones
      Javad Chegini Hamid Reza Darvishvand Hossen azimi chamani
      Today analyzing seismicity hazard urban different areas is critical and inevitable due to develop and to expand cities in seismically active zones and naturally, the hazard because the earthquake is more in the bigger cities and the necessity to consider these hazards w More
      Today analyzing seismicity hazard urban different areas is critical and inevitable due to develop and to expand cities in seismically active zones and naturally, the hazard because the earthquake is more in the bigger cities and the necessity to consider these hazards would be increased. Expanding the cities in Iran seismically active zones caused to be necessary to analyze earthquake hazard. Bouinzahra, Qazvin and Hamedan as cities in subject to earthquake hazard are perfect relevant instances. These important cities have been surrounded among active faults and it’s possible always to happen a big earthquake on it. For probabilistic risk analysis for different levels of software EZF RISK that a program is incredibly strong in this field has been used. This study analyzes the seismic hazard of earthquake for these 3 cities considering this truth by Probabilistic and Deterministic analyzing method. The results showed the relative level of earthquake hazard is high in these cities and it’s according to suggesting opinion of Iranian code of practice for seismic resistant design of buildings (2800). Manuscript profile
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      105 - Evaluating Response Modification Factors of Concentrically Braced and Special Moment Steel Frames in Duplex Buildings
      Leila Kalani Sarokolayi Sirous Gholampour dehkordib Masoud Shafaghati sefidabc
      Response modification factor (R-factor) is one of the seismic design parameters to consider nonlinear performance of building structures during strong earthquake. Relying on this, many seismic design codes led to reduce earthquake loads imposed to the structure. The pre More
      Response modification factor (R-factor) is one of the seismic design parameters to consider nonlinear performance of building structures during strong earthquake. Relying on this, many seismic design codes led to reduce earthquake loads imposed to the structure. The present paper tries to evaluate the R-factors of conventional concentric braced frames (CBFs) and special moment frames (MRFs) in duplex steel buildings with level difference in their floors. Since, the R-factor depends on ductility and over strength, the incremental nonlinear static analysis, push over analysis, has been performed on 4, 7 and 10 storey building models with three floor level differences and including CBFs and special MRFs systems in x and y directions of buildings respectively. The results showed that the R-factors for CBFs system in duplex buildings were higher than ones in conventional buildings without floor level differences while for MRFs system it was found that on 4 and 7 storey duplex buildings, the R-factors were decreased and with the increase in building height to 10 storey, they were increased compared to conventional models. Manuscript profile
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      106 - Studying the Effect of Horizontal Drains on Stability of Heterogeneous and Homogeneous Earth Dams during Rapid Drawdown Condition
      Alireza Hajiani Boushehrian Azadeh Rezaee Arash Vafamand
      One of the main concerns to design earth dam is the stability of the upstream slope of the earth dam in phase of rapid drawdown. Confined pore water pressure reduces the effective stress in this mode, so possibility of the instability and slippage will be increased. The More
      One of the main concerns to design earth dam is the stability of the upstream slope of the earth dam in phase of rapid drawdown. Confined pore water pressure reduces the effective stress in this mode, so possibility of the instability and slippage will be increased. The main goal of this research is to investigate changes in the pore water pressure by using horizontal drains in upstream slope of the earth dams and the improvement in case of the factor of safety. In this study, firstly, the homogeneous and heterogeneous modes of the earth dam are considered and then rapid drawdown mode are modeled in two upstream slope modes without the horizontal drain and with the upstream slope including up to seven horizontal drains. These two modes are modeled by using GEOSTUDIO software. According to the obtained results, improvement by horizontal drains leads to increase in dissipation of pore water pressure and also increase the stability of the safety factor of the upstream slope up to 24% for homogeneous dams and 17% for heterogeneous dams. Practical equations were also presented to show the relation between the numbers of horizontal drains, the factor of safety and the pore water pressure. In order to study the influence of the horizontal drains on the upstream slope of the earth dams during the rapid drawdown condition, Molasadra earth dam geometry is used both in the modes of homogenous and heterogeneous dam. Molasadra dam and power station is located in about 13 kilometers of southwest of Sadeh county, around of Eghlid town in the north of Fars province in Iran. Manuscript profile
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      107 - Concrete Debris Recycling, Environmental and Economic Effects
      Ali Binaei Haghighi Leila Shahryari
      In this paper, first we identify the destruction ways of concrete constructions and the benefits of waste management and the plans to recycle the concrete debris were investigated and it was concluded that the existence of plans to recycle the concrete debris could lead More
      In this paper, first we identify the destruction ways of concrete constructions and the benefits of waste management and the plans to recycle the concrete debris were investigated and it was concluded that the existence of plans to recycle the concrete debris could lead to big economic save ups and by recycling these debris we can create affordable ways for concrete making centers. By the way, by increasing the recycling of such this debris, we can reduce the use of natural resources and help the environment. Manuscript profile
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      108 - Investigation of Liquefaction Mechanism in Double Sand Lenses
      Y. Pashang pisheh
      In many cases of heavy earthquakes, liquefaction has resulted in serious damages. Existing anisotropy in soil layers results in some difficulties to realize the reason for these phenomena. Loose sand lenses buried in fine soils are one of the cases which may result in t More
      In many cases of heavy earthquakes, liquefaction has resulted in serious damages. Existing anisotropy in soil layers results in some difficulties to realize the reason for these phenomena. Loose sand lenses buried in fine soils are one of the cases which may result in these problems and as a weak point during the earthquake can cause this phenomenon. In this paper, using FLAC 2D software, double sand lenses liquefaction mechanism and soil deformation due to applying cyclic loading has been studied and investigated. The FLAC software that has been used for analyzing is capable of modeling progressed models of soil and loading under different conditions. Manuscript profile
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      109 - The Prevention of Environmental Damage in Durable Unsymmetrical Huge-capacitors Based on MnO2 and Fe2O3 Nanotubes
      M. Ebrahimi seyed Ali Haj Seiyed Taghia
      The prevention of environmental damage in durable unsymmetrical huge-capacitor (UHC) with α-MnO2 nanotubes and amorphous Fe2O3 nanotubes grown on flexible carbon fabric is first designed and fabricated. The assembled novel flexible UHC device with an extended oper More
      The prevention of environmental damage in durable unsymmetrical huge-capacitor (UHC) with α-MnO2 nanotubes and amorphous Fe2O3 nanotubes grown on flexible carbon fabric is first designed and fabricated. The assembled novel flexible UHC device with an extended operating voltage window of 1.6 V exhibits excellent performance such as a high energy density of 0.55 mWh/cm3 and good rate capability. The UHC devices can find numerous applications as effective power sources, such as powering color-switchable sun glasses and smart windows. Manuscript profile
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      110 - Derivation of Equation of Motion for the Pillow-Shape Seismic Base Isolation System
      Ali Tayaran Mahmood Hosseini
      Rolling-based seismic isolation systems, in which rollers of circular or non-circular section are used, are less expensive and easier to manufacture. However, this type of isolation suffers from either lack of restoring or re-centering capability, or weakness against up More
      Rolling-based seismic isolation systems, in which rollers of circular or non-circular section are used, are less expensive and easier to manufacture. However, this type of isolation suffers from either lack of restoring or re-centering capability, or weakness against uplift forces. To resolve the first shortcoming the use of elliptical as well as pillow-shape rolling parts has been suggested, and for the second one, using some uplift restrainers has been proposed. In this paper a kind of base isolating device, called Pillow-Shape Seismic Base Isolation System (PSBIS) is introduced which has both re-centering and uplift-restrained capabilities. The paper is concentrated on derivation of equation governing the motion of PSBIS device. To derive this equation, since the behavior of the device is highly nonlinear the use of Lagrange equation of motion is the most appropriate approach. For this purpose, considering the rotation angle of the pillow-shape roller as the generalized coordinate, the horizontal and vertical components of the pillow-shape roller acceleration have been formulated and the kinetic and potential energy terms as well as the virtual work of the non-conservative, resulted from rolling resistance and seismic forces, have been developed to be substituted in the basic Lagrange equation. To verify the derived equation of motion a simplified sample of the PSBIS device was built and used experimentally, and also the motion of the pillow-shape parts was traced by drawing them in Auto-CAD software. Results show the validity of the derived equation of motion. Manuscript profile
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      111 - Investigative and Comparative Approach for Worldwide Information and local perceptions Induced by Climate Change and its Correspondence
      Abbas ali Tayefi Nasrabadi Atefeh Dehghan Touranposhti
      A new challenge which the world will face in near future is the reduction of water resources regarding to global climate changes. Climate change is one of the phenomena which will threats future of the universe. Iran locates in an arid and semi-arid region and has limit More
      A new challenge which the world will face in near future is the reduction of water resources regarding to global climate changes. Climate change is one of the phenomena which will threats future of the universe. Iran locates in an arid and semi-arid region and has limited water resources. Based on global and Intergovernmental Panel on Climate Change (IPCC) board database and the statistics of some selected synoptic stations (Tabriz, Bilghan, Mashhad) to obtain an appropriate spatial distribution in northern part of the country, we have considered the climate change and its effects on Iran`s water resources. Based on IPCC scenarios the temperature will grow 1-2 degrees in these regions till 2020 and precipitation will decline to 20%, this will directly influence the condition of water resources of these regions and new challenges. This procedure and its changes will be considered through statistical analysis and graphical description of data gathered through selected synoptic stations databases. Regarding climate changing effects on water resources, studying the karst water resources of Northern Khorasan indicated a significant reduction among the springs' discharge in these resources. Manuscript profile
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      112 - Determination of Lateral load Capacity of Steel Shear Walls Based on Artificial Neural Network Models
      Meisam Bayat Ali Delnavaz
      In this paper, load-carrying capacity in steel shear wall (SSW) was estimated using artificial neural networks (ANNs). The SSW parameters including load-carrying capacity (as ANN’s target), plate thickness, thickness of stiffener, diagonal stiffener distance, hori More
      In this paper, load-carrying capacity in steel shear wall (SSW) was estimated using artificial neural networks (ANNs). The SSW parameters including load-carrying capacity (as ANN’s target), plate thickness, thickness of stiffener, diagonal stiffener distance, horizontal stiffener distance and gravity load (as ANN’s inputs) are used in this paper to train the ANNs. 144 samples data of each of this parameters was calculated using SSW simulation in abaqus. Load-carrying capacity of SSW was estimated using radial basic function (RBF) and multi-layer perceptron (MLP) neural networks. Spread parameter in RBF and number of hidden layer, number of neurons in this layers and activation function in MLP optimized using a trial and error method. The results showed that the load-carrying capacity of SSW could estimate using RBF and ANN by 84 and 96 percent of precision respectively. Manuscript profile
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      113 - Assessment of the Effects of Geological Formation on the Water Resources Quality in Arid and Semiarid Watersheds
      Naser Shamskia H. R. Payrovan
      One of the most important subjects in relation of water resources quality in the many of river is the chemical composition of waters and conservation of water quality in the watershed. Geological formations in any region of the earth are the main surface and foundation More
      One of the most important subjects in relation of water resources quality in the many of river is the chemical composition of waters and conservation of water quality in the watershed. Geological formations in any region of the earth are the main surface and foundation that water flows on the bed and strata of formation, which in fact they affect their characteristics on water quality as positive or negative effects. The effect of various geological formations analyzed from Pre-Cambrian to recent Era in some of region in Iran. To show their effects on water quality on a few of water rivers, and therefore to classified these formations, they divide into two separate groups; desirable and undesirable formations. It is necessary to classify them depend on their resistance against weathering and erosion. Influence of these two agents on geological formations will produce the material which effects on water quality that considered in this paper, it have been assessed and explained. There are many cases of river in different regions in Iran such as lower stream Karoon, Qezel-uzan, Qom-Rud River, and etc..., in which they passed and flow in the Neogene formations, and they have changed the water quality of rivers. It is notable that this study can be useful in river engineering, dam construction, flood spreading, rain water harvesting and transmission of water for drinking or agriculture targets. Manuscript profile
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      114 - Influence of the Isolator Characteristics on the Response of the Isolated Buildings in the Near-FaultEarthquakes
      Beytollah Taromi Kiarash Nasserasadi Asghar Vatani Oskouei
      Seismic base isolation are devices that used to limit the human and material damage caused by an earthquake. This devices diffuse the energy induced at the time of the earthquake before being transferred to the structure.The base isolated structures when subjected to th More
      Seismic base isolation are devices that used to limit the human and material damage caused by an earthquake. This devices diffuse the energy induced at the time of the earthquake before being transferred to the structure.The base isolated structures when subjected to the near-fault eathquakes which contain long-period velocity pulses that may coincide with the period of base isolated structures resulting in excessive deformation and rupture of isolators. Parameters of base isolation such as the yield strength and post yield stiffness ratio have significent effect on the displacement of isolation system. To study this effect, influence of these parameters on the dynamic response of the isolated structures in term of displacment, acceleration, base shear and absorbed energy has been studied. The results show that the increase in the bearing yield strength can reduce the bearing displacment signficantly without much alterning to the superstructure accelerations. Also the optimum yield strength and post yield stiffness ratio of the LRB is found to be in range of 0.8% - 1% of the total weight of the building and 0.08 – 0.12 of the ratio of plastic stiffness to elastic stiffness of base isolation respectively under near fault motions. Manuscript profile
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      115 - Evaluation and Comparison of LEED, BREEAM, and the 19th issue of National Building Regulations of Iran (NBRI) in Perspective of Sustainability by (MCDM) TOPSIS Method
      Mohammad Javad Mahdavinejad Mohammad Mehranrad Nasim Eslamirad
      In this research, the features of LEED, BREEAM, and NBRI also, their principles, are reviewed, evaluated, and compared from the aspects of the sustainability. The compliance items of standards with the principles of sustainability determine that their goals are well mat More
      In this research, the features of LEED, BREEAM, and NBRI also, their principles, are reviewed, evaluated, and compared from the aspects of the sustainability. The compliance items of standards with the principles of sustainability determine that their goals are well matched. By comparing the different and shared principles, it discovered how each standard has succeeded from the aspect of the sustainable design also, the shortcomings in the 19th issue of NBRI were appeared. The evaluation of standards with sustainability principles is done by applying (MCDM) TOPSIS. furthermore, by ranking each sub-item of standards from weak to excellent, the respect of sustainability principle is recognized. plus, according to the TOPSIS and analyzing the data, any items of each standard has the most sustainability feature are considered. The alignment with the leading tools can result in the promotion of the Iranian regulations. Findings of this research provide suggestions for completing and localizing the criteria that are part of the LEED and BREEAM in energy section which are neglected in the 19th issue. Applying these solutions and paying more attention to all of building's sustainable aspects in Iran will lead to the success of the country to be adopted with the global counterparts. Manuscript profile
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      116 - Investigation of Liquefaction Mechanism and Displacement in Buried Sand Layers
      Y Pashangpisheh
      One of the most important reasons for damages during earthquakes is the liquefaction of loose and saturated sand soils. However, in many regions with proper soil specifications, the large settlements have been observed in the ground surface. Loose sand layers buried in More
      One of the most important reasons for damages during earthquakes is the liquefaction of loose and saturated sand soils. However, in many regions with proper soil specifications, the large settlements have been observed in the ground surface. Loose sand layers buried in fine soils are one of the cases which may result in these problems and as a weak point during earthquake can cause this phenomenon. In this paper, the behaviour of buried sand layer affected by cyclic loading and its deformation during liquefaction has been studied and investigated using FDM. Then, the results have been compared with those of other investigators. Based on comparisons, the deformation of liquefied layer resulted in current study is in a good agreement with experimental methods proposed by “Seed-Tokimatsu” and “Ishihara-Yoshimine”. Manuscript profile
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      117 - The Generation of Earthquake PGA Using Stochastic Finite Fault Method in Alborz Region
      Ali Delnavaz Mohammad Ali Habibzadeh Ali Hajsayedtaghiya
      Time-history analysis is defined as a kind of dynamic analysis increasingly used in design of structures and evaluation of existing ones. One of the important issues in the Time-history analysis is selecting earthquake records. In this case, seismic design provisions st More
      Time-history analysis is defined as a kind of dynamic analysis increasingly used in design of structures and evaluation of existing ones. One of the important issues in the Time-history analysis is selecting earthquake records. In this case, seismic design provisions states that time histories shall have similar source mechanisms, geological and seismological features with region under study. Alborz is one of the highly seismic regions of Iran which records of large events are not sufficiently available. For this reason, the main objective of this research is to modeling strong motion records and comparing those with observed records. For modeling strong motion at a particular site three main elements: regional earthquake source, propagation path effects and local site conditions should consider. In this study stochastic finite fault approach for generation earthquake accelerographs was used. The use of a finite fault model is particularly important in improving the reliability of estimates for large-magnitude events at close distances. Finally after comparing the results, the generated records are found to be consistent with observed records in Alborz region. Manuscript profile
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      118 - Case study of the statistical distribution of the concretes implemented at Qazvin
      Ali Ebrahimi Mahdi Mahdikhani
      Characteristics of produced concrete become changedthrough changingthe characteristics of materials constituting the concrete. These changes include: The quality of cement, the real ration of water to cement: with neglecting the further water within the aggregates or la More
      Characteristics of produced concrete become changedthrough changingthe characteristics of materials constituting the concrete. These changes include: The quality of cement, the real ration of water to cement: with neglecting the further water within the aggregates or lack of that, the consideredratio fluctuates and the characteristics of the aggregate which are related to the following dimensions: quality of aggregate, shape of aggregate and aggregate grading. The calculated strength in the mix design is the mean target strength which is marginally further than the specified strength. This further margin lowers the ration of water to cement in calculations and consequently, for a stable flow, the amount of consumption or alloy of cement in concrete increases. On the other hand, the amount of the margin depends on the following factors: The sensitivity level of the concrete project (with K coefficient) and standard deviation of concrete production. The purpose of defining this laboratory project is to obtain an optimal concrete mix design for different consumptions and consequently comparison of theoretical and workshop results in the mix design, lowering the cement consumption and the costs of concrete productions in batching and increasing or stabling the specified strength of concrete through lowering the level of cement consumed in concrete. In this procedure, concrete is produced through common method that is segregating sand from cement to compare that with the results obtained, and to calculate standard deviation fall, strength margin and cement alloy fall in order to produce concrete which is statistically suitable for the required strength. Manuscript profile
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      119 - Determining the Likelihood of Damage in Concrete and its Physical Structure
      leila Shahryari
      Applying renormalization group theory to evaluate the safety of overall structure, local damage probability must be obtained at first. According to the results of unit detection test and numerical simulation, the methods how to determine local damage probability was pre More
      Applying renormalization group theory to evaluate the safety of overall structure, local damage probability must be obtained at first. According to the results of unit detection test and numerical simulation, the methods how to determine local damage probability was presented in the paper. For small unit, meaning the unit size is far less than the maximum primitive cell or the structure size, if the unit is damaged by detection test, the local damage probability of it is defined as 1. Otherwise it is defined as 0. For large unit, the local damage probability is expressed by the ratio of volume summation of all damages to volume of the unit. The process of local damage probability to be obtained was also introduced. Based on the results of numerical simulation, the local damage probability how to be obtained was mainly expounded. Concrete strength was assumed to obey two parameter Waybill distributions. Therefore, damage probability based on stress of concrete structure may be developed to obey it. The steps of obtaining local damage probability are stated. Furthermore, determination of parameters was introduced in similar structure. Manuscript profile
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      120 - A Comparison between Different Editions of API650 Seismic Provisions for Cylindrical Steel Storage Tanks Considering the Fragility Curves
      Hooman Fili
      Seismic safety of liquid storage tanks is of considerable importance due to its application in different industries. In Iran, most of these storage tanks are designed based on API650 code provisions. Despite designing tanks according to API standard, the lesson learned More
      Seismic safety of liquid storage tanks is of considerable importance due to its application in different industries. In Iran, most of these storage tanks are designed based on API650 code provisions. Despite designing tanks according to API standard, the lesson learned from previous earthquakes, shows different kind of damage occurring on them. This study is an investigation on evaluating different revisions of API650 seismic codes from years 2001 to 2013. The failure modes considered are Buckling, Overturning, Sliding and Shell Yielding. For this, three steel cylindrical tanks has been checked by different revisions of API650 under different PGA from 0.1 to 2 and various failure modes are taken into account respectively for each tank. According to these information, the fragility curves are derived and compared among all the revisions of API650 code. According to the resultsit seems that API650 in edition of 2001, Presents buckling criteria as the main criterion.This criterioncompared to the overturning criteria even in unanchored tanks determinedvery conservative.In these samplesthere were no overturning criteria prior. In 2005, 2009 and 2013 editions of API650 for unanchored tanks, presented overturning criteria as the main criterion considering the sliding and total stress failure criteria but for anchored tanks total stress failure criteria controlled much more conservatively. Generally buckling criteria not reported in prior. Manuscript profile
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      121 - The Investigation of Effective Factors in the Removal of Bentonite Jelly from the Joints of Cut-off Wall Panels
      Seyed Majdeddin Mir Mohammad Hosseini Abdolhossein Azadmaneshb
      In the construction process of a plastic concrete cut-off wall, concreting is usually performed using the termie pipe method. In this method, concreting is performed from the lowest point in the excavated trench (containing the slurry) using a funnel and the pipe connec More
      In the construction process of a plastic concrete cut-off wall, concreting is usually performed using the termie pipe method. In this method, concreting is performed from the lowest point in the excavated trench (containing the slurry) using a funnel and the pipe connected to it. The concrete poured in the funnel gradually settles in the panel through the termie pipe which is beneath the slurry and the end of the pipe has always been in the concrete. Because of its unit weight which is less than that of the concrete, the slurry goes up and the height of its column reduces. As the construction continues the length of the termie pipe is cut down so that the remaining operation is carried out more easily. In this process there are three types of flows to be considered: concrete flow in the termie pipe, concrete flow in the panel and slurry flow in the panel. Using the fundamentals of hydraulics, this paper tries to study the interactions among these fluids. It also examines the influential factors in removing the bentonite jelly in order to provide the plastic concrete with homogeneity and consistency (slump 22-16 cm) in primary and secondary panels of cut – off wall as a most reliable water tightening system in most dam foundations. Manuscript profile
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      122 - Presentation of Empirical Relation for the Fundamental Period of Irregular Steel Frames with EBF Steel Braces
      F. Omidinasab S. Baharipour
      Developments in the field of Structure and Earthquake Engineering and also consequences of earthquakes have been led to develop some continually changes and improvement of seismic regulations around the world. In regards to seismicity of Iran, it is necessary and also p More
      Developments in the field of Structure and Earthquake Engineering and also consequences of earthquakes have been led to develop some continually changes and improvement of seismic regulations around the world. In regards to seismicity of Iran, it is necessary and also possible to review and edit the Seismic Regulations of Iran and compare it with the other countries; so it seems that a comparative study of relations of the fundamental period based on various regulations is required. This debate is regarded to change all kinds of structures; for example, here the irregular structures with varieties of irregularities on height can be mentioned. The irregular structures are more observable than the other ones because of their unique form and creative ideas of architectures. Then, in regards to extend and grow of usage these structures around the country we shall collect and present a correct study based on an accurate planning because investigation of the fundamental period of irregular steel frames on height is required. By this research the investigation of the fundamental period of three-opening irregular steel frames with divergent bracing along with irregularities on height is studied. Models of three-bay frames with 2-15 storeys have been modeled by Etabs Software; also a series of short, middle and high frames have been modeled by Opensses Software, and then they are compared together, finally the analyzed periods have been compared with the different relations in Regulation; then by the use of MATLAB-2013 Software some coefficients of formula of the fundamental period have been determined for three-bay frames with one-sided-stepped on the height and divergent bracing. Manuscript profile
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      123 - An Optimization Model for Financial Resource Allocation Towards Seismic Risk Reduction
      Elnaz Peyghaleh M.R. Zolfaghari P. Vaziric
      This paper presents a study on determining the degree of effectiveness of earthquake risk mitigation measures and how to prioritize such efforts in developing countries. In this paper a model is proposed for optimizing funds allocation towards risk reduction measures (b More
      This paper presents a study on determining the degree of effectiveness of earthquake risk mitigation measures and how to prioritize such efforts in developing countries. In this paper a model is proposed for optimizing funds allocation towards risk reduction measures (building retrofitting) and reconstruction process after potential earthquakes in a regional level. The proposed model seeks optimized strategy towards risk reduction based on minimizing or maximizing various criteria such as retrofitting costs, economic damages including business interruption losses, number of human casualties and other seismic hazard consequences. The main objective of this model is to find optimum strategy for maximizing the benefits of available economic resources for retrofitting and reconstructions. Regional seismic hazard and building stocks and their vulnerability functions are used to model probabilistic seismic risk for a given region. The proposed model is adjusted for developing countries exposed to high seismic sources like Iran. In order to present the application of the proposed method, the approach is applied for a pilot area in Tehran. Results illustrate the variation of mitigation in particular, structural retrofitting expenditures and reconstruction expenditures by structural type for buildings in this region. In addition, recommended expenditures by year for the case study are obtained according to the results. Manuscript profile
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      124 - Buckling of Cylindrical Steel Shells with Random Imperfections due to Global Shear
      Nima Rahmani Mehran S. Razzaghi Mahmoud Hosseini
      This study aims to investigate the effects of geometric imperfections on buckling of thin cylindrical shells due to global shear. To this end, more than 320 finite element models of cylindrical shells with different diameter to thickness ratios were prepared. Random imp More
      This study aims to investigate the effects of geometric imperfections on buckling of thin cylindrical shells due to global shear. To this end, more than 320 finite element models of cylindrical shells with different diameter to thickness ratios were prepared. Random imperfections with different amplitudes were applied to numerical models. The results revealed that global buckling of cylindrical shells are susceptible to imperfection patterns. It was also shown that Yamaki’s expression can be considered as upper band for plastic shear buckling of thin cylindrical shells. Manuscript profile
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      125 - Developing a Cost-Effective Approach for Enhancing the Rheological and Mechanical Behavior of High Strength Self-Compacting Concrete
      Sahand Mardi Morteza Bastami
      Despite the numerous advantages of using concrete with high strength capacity, the brittle behavior of high strength concrete (HSC) and higher production cost has limited its use in the construction industry. This research aims to develop a cost-effective approach for p More
      Despite the numerous advantages of using concrete with high strength capacity, the brittle behavior of high strength concrete (HSC) and higher production cost has limited its use in the construction industry. This research aims to develop a cost-effective approach for production of high strength self-compacting concrete with desirable performance in either compressive or tensile loading condition. To reach this purpose, 18 mixtures were cast initially with different w/c, binder, and silica-fume percentages. The results show that it is possible to produce high strength self-compacting concrete economically without using any additives such as silica-fume. Afterward, an innovative reinforcing technique using hexagonal wire mesh (HWM) were introduced for enhancing the HSC performance. The results show that HWM is able to enhance HSC behavior in both tensile and compressive loading condition. Finally, an economic analysis was conducted and the optimum HWM properties are selected according to the analysis results. Manuscript profile
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      126 - Seismic Vulnerability assessment of concrete railway bridge using nonlinear analyses
      Araliya Mosleh Hamed Hamidi Ahmad Nicknam José Jara Humberto Varum
      Bridges, as an essential part of transportation system, play a special role in economy, politic and military all around the world. Serviceability of bridges is of high importance especially in emergencies, helping injured people and proportioning transportation after ea More
      Bridges, as an essential part of transportation system, play a special role in economy, politic and military all around the world. Serviceability of bridges is of high importance especially in emergencies, helping injured people and proportioning transportation after earthquakes. Earthquake regulation codes, normally suggest linear methods to conduct the analysis, and nonlinear analysis is barely used by practicing engineers. In this paper, we analyze a typical concrete bridge located in Iran and use both nonlinear dynamic and static procedures at two hazard levels. This study compares both methodologies, analyze the results and presents some recommendations to reduce the seismic vulnerability. Manuscript profile
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      127 - A Numeral Research on Effect of Vertical Component of Near Field Earthquakes on Long Span Bridges Built on Different Soil Conditions
      Ali Delnavaz Hasan Aghabarati Ali ShiriTorkamani
      In this study we tried to consider effect of vertical component of near zone earthquake (10 to 15 km far from fault) such as Kobe 1995, Northridge 1994, Loma prieta 1989 and Chichi 1999 on a concrete cable bridge by a 320m span in the middle which was built on different More
      In this study we tried to consider effect of vertical component of near zone earthquake (10 to 15 km far from fault) such as Kobe 1995, Northridge 1994, Loma prieta 1989 and Chichi 1999 on a concrete cable bridge by a 320m span in the middle which was built on different type of soils. The SAP software (version14) was selected because I should have done linear and non-linear time history analysis by defining plastic hinges. Also we achieved to some results depended on types of soils and finally we extracted some factors for dead load to consider effect of vertical component of earthquakes on axial force, shear force and bending moment of different parts of the structure, also we gathered some results about horizontal and vertical displacement of span in the middle. Manuscript profile
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      128 - The Effect of Lower Detachment Zone on Buckle Folds Geometry
      O Barani
      Buckle folds are common traps for hydrocarbon in several contractional provinces. Buckle folds form where stratified sequences rest a top salt or some other utterly weak rock as a decollemet zone in units with high competency contrasts by a compressive stress which acte More
      Buckle folds are common traps for hydrocarbon in several contractional provinces. Buckle folds form where stratified sequences rest a top salt or some other utterly weak rock as a decollemet zone in units with high competency contrasts by a compressive stress which acted along the length of the rock layers. An important parameter affecting buckle folding of a competent zone above a mobile decollement is existence of a thick lower decollemet. In this paper the effect of detachment zone on folding of rock layers is studied using finite element method. Large deformation formulation is considered. Mohr-Coulomb plasticity model is used to deal with nonlinearity of material during folding. Two cases of folding are considered. In the first case a symmetric fold with equal detachment thickness beneath two flanks is analyzed. In the second case detachment zone is omitted in one flank. Finally, the effect of detachment zone on folding and deformed shape of buckle fold is studied. Manuscript profile
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      129 - Investigating the Effect of natural Pozzolans on Mechanical Properties of Roller Compacted Concrete
      Mohammad Falahnejad Mahdi Mahdikhani
      Roller Compacted Concrete (RCC), is a concrete with zero slump, which is used in damming and road pavement. Roller Compacted Concrete Pavement (RCCP) bear heavy traffic loads and severe weather conditions. This type of concrete is due to its economic and environmental c More
      Roller Compacted Concrete (RCC), is a concrete with zero slump, which is used in damming and road pavement. Roller Compacted Concrete Pavement (RCCP) bear heavy traffic loads and severe weather conditions. This type of concrete is due to its economic and environmental capabilities, including reduced construction and maintenance costs, longer durability and longer lifetime, as well as environmental compatibility. This paper presents the results of laboratory studies on the effect of natural pozzolan (zeolite) on the mechanical properties of RCC specimens. In this study, cement materials of were used The rheological performance test (VeBe) and compressive and tensile strengths at the age of 7, 14 and 28 days and the flexural strength tests at 14 and 28 days were performed on the specimens. The results show that the higher amount of pozzolan reduced concrete efficiency (the time of VeBe increased). In addition, the compressive, tensile and flexural strength of the samples are decreased, significantly. However, reducing resistance does not mean compliance with the requirements of the Code. Manuscript profile
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      130 - Analysis of Circular Reinforced Tunnels by Analytical Approach
      Ahmad Fahimifar Masoud Ranjbarnia
      This paper addresses the problem of quantifying the mechanical contribution of rockbolts installed systematically around tunnels (regularly spaced around the tunnel) excavated in rock masses. Assuming that the mechanical contribution of grouted rockbolts is that of incr More
      This paper addresses the problem of quantifying the mechanical contribution of rockbolts installed systematically around tunnels (regularly spaced around the tunnel) excavated in rock masses. Assuming that the mechanical contribution of grouted rockbolts is that of increasing internal pressure within a broken rock mass, a new procedure for computation of ground response curves for a circular tunnel excavated in strain softening material and then reinforced with systematically active grouted rockbolts is presented. In this work, the equation of the ground response curve for a tunnel which has been reinforced with passive grouted rockbolts is also derived. The proposed model allows one to take into account the effect of the distance of the bolted section to the tunnel face, the effect of increasing rockbolts spacing, the influence of increasing pretension load in calculating of the ground response curve, and the effect of increasing the cross-section area of rockbolts. The results show that decreasing rockbolts spacing increases the support system stiffness rather than preloading of them. Manuscript profile
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      131 - Assessment of Subsurface Explosion caused byTunnel Construction in Urban Areas
      Hossein Haghighimanesh Mohammad Azadi
      Nowadays, tunneling in urban areas is a common activity for a variety of transportations such as subways, water supply, lifelines andsewers that may require blast operations. The characteristics of stress waves of the blast are quite different from earthquake waves. The More
      Nowadays, tunneling in urban areas is a common activity for a variety of transportations such as subways, water supply, lifelines andsewers that may require blast operations. The characteristics of stress waves of the blast are quite different from earthquake waves. The blast waves are usually of high frequency content, short duration, equality of amplitudes in horizontal and vertical directions and large range of magnitude from ten to thousands of the gravitational constant. However few papers can be found to discuss about the effect of soil characteristics under blast loading. In this paper, numerical models based on finite element method is used to simulate stress wave at soil sites under explosion effect in an underground linear chamber and then characteristics of the ground movement and the explosion effect on soil-structure interaction is analyzed. In this study, numerical results of area deformations in every region are compared together and parameter sensitivity of the soil is analyzed. Results presented in this paper can be used in a more detailed assessment of ground motion effect on structures. Manuscript profile
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      132 - Investigation of forward directivity effects on design spectra of industrial complexes near Assaluyeh fault
      Ali Raoof Mehrpoor Masoud N. Ahari
      Recorded ground motions in near fault region have completely distinct nature from others that recorded in far field of the fault. Near source outcomes cause much of the seismic energy to appear in a single large and long period pulse at the beginning of the velocity rec More
      Recorded ground motions in near fault region have completely distinct nature from others that recorded in far field of the fault. Near source outcomes cause much of the seismic energy to appear in a single large and long period pulse at the beginning of the velocity record. Assaluyeh complex is located near the reverse Assaluyeh fault that is a segment of Mountain Front Fault. This complex contains facilities which have a wide range of structural periods. Effects of this vicinity on seismic hazard of this region can be considered by using approaches which incorporate effects of near fault in seismic hazard analysis. It can be achieved by using near source specific ground motion models in probabilistic seismic hazard analysis and using accelerograms which contain the pulse-like effects of forward directivity. The results indicate that the site-specific design spectra ofthis study fall at an upper level in comparison with the standard design spectra of Iranian 2800 standard and the specific design spectrum of International Institute of Earthquake Engineering and Seismology (IIEES). It is worth noting that near fault effects should be considered in probabilistic seismic hazard analysis and preparation of site specific design spectra if the site is located near source region of a fault. Manuscript profile
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      133 - The Effect of Compressive Strength Reduction of Column Section Expose due to Freezing-Thawing Cycles on the Seismic Performance of Bridges
      Saeideh Alsadat Mousavi Mehran Seyed Razzaghi
      One of the serious damages of tremendous earthquakes is the damage to bridges as the major components in an arterial road network, as relief operation is interrupted following cutting roads. Regardless of the magnitude and severity of an earthquake, other factors are al More
      One of the serious damages of tremendous earthquakes is the damage to bridges as the major components in an arterial road network, as relief operation is interrupted following cutting roads. Regardless of the magnitude and severity of an earthquake, other factors are also important in the strength and seismic performance of concrete bridges. Freezing-thawing cycles are among the factors, which erode the piers of concrete bridges over time. Therefore, it is necessary to evaluate the seismic vulnerability of bridges for future designs.This research aims at discussing the effect of freeze-thaw cycles on the seismic performance of concrete bridges using fragilitycurves. Fragility curves express the conditional probability to reach or exceed a level of damage as a function of ground motion parameters. The curves have been developed analytically using a probabilistic method. Ground motion parameter, peak ground acceleration, structural criterion, and relative displacement of piles were considered. The non-linear time history analysis in OpenSees was used for demand determination. The curves were drawn for the slight, moderate, and extensive damage levels in two modes of before and after damage caused by thawing and freezing, i.e. the mode in which the compressive strength of column section expose reduced. With respect to the fragility curves, the strength reduction increases bridge vulnerability, especially on slight damage levels. Comparing with the cyclic curves of the most vulnerable column in two modes of before and after the damage showed that energy absorption capacity lowered with the expose compressive strength reducing. Manuscript profile
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      134 - Effect of the Cylindrical Reinforcing Element’s Filling Materials on the Soil’s Resistance
      Seyed Vahid Mojtahed Sistania Soheil Ghareh Mehdi Siavoshnia
      In this paper a laboratory study has been carried out on the effect of changing the type of soil filling cylindrical reinforcing elements from SM to GM on behavior of sandy soil. In this study the primary tests for evaluation of the impact of reinforced sand and gravel More
      In this paper a laboratory study has been carried out on the effect of changing the type of soil filling cylindrical reinforcing elements from SM to GM on behavior of sandy soil. In this study the primary tests for evaluation of the impact of reinforced sand and gravel columns with diameters of 5 cm and heights of 15 cm subjected to vertical stresses of 50, 100, and 150 KPa were carried out in a large-scale direct shear apparatus (300×300×150 mm). Results showed that the shear stress and settlement of the reinforced sample with geogrid and a gravel column increases by 45.4% and decreases by 23.9% respectively compared to the non-reinforced sample. Manuscript profile
    • Open Access Article

      135 - The Study of Improvement of Dispersive Soil Using Magnetic Field
      S. F Ashrafi M Behzad A Naseri H Ghafarian Malmiri
      In this study, the feasibility of using magnetic technology to reduce the dispersion of soil has been investigated. The reference treatment was potable water and 3 magnetic water devices (with different magnetic intensities) were used for magnetizing the potable water. More
      In this study, the feasibility of using magnetic technology to reduce the dispersion of soil has been investigated. The reference treatment was potable water and 3 magnetic water devices (with different magnetic intensities) were used for magnetizing the potable water. The results showed that the magnetic field has a significant effect in order of 5 percent on increasing of magnesium concentration in soil columns and the calcium concentration in magnetic treatment was more than the reference treatment. It seemed that improving in hydrogen bonding between water molecules and clay particles and water trapping in soil caused reduction of salt in the soil. According to the increase of calcium and magnesium bivalent Cations in the soil, it is suggested that the use of magnetic field could improve soil’s dispersion and decrease the degree of soil’s dispersion. Manuscript profile
    • Open Access Article

      136 - Evaluation of Seismic Performance of Combined Horizontal and Vertical Hexagrid Structural System for High-rise Buildings
      Yasaman Memarzadeh Kiani Maryam Firoozi Nezamabadi
      Summary In this study, the seismic performance of hexagrid structures which are composed of horizontal and vertical hexagrid by using a transitional story, has been investigated. To this end, 10 models of 50-story hexagrid structures were designed. 9 models with horizon More
      Summary In this study, the seismic performance of hexagrid structures which are composed of horizontal and vertical hexagrid by using a transitional story, has been investigated. To this end, 10 models of 50-story hexagrid structures were designed. 9 models with horizontal hexagrid cells which transited to vertical cells using a transitional story, and a model of completely horizontal hexagrid have been designed. Finally, the seismic performance of these models were investigated and compared to the horizontal hexagrid structure to obtain the optimum location of the transitional story. According to the analyses results, combining horizontal and vertical hexagrid cells can strongly affect the seismic performance of the structure. Thus, choosing the optimum location of transitional story, regarding design priorities, is of significant importance. Manuscript profile
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      137 - Evaluation of Nonlinear Response of Structures to Near-Fault Ground Motions and the Comparison of Results with Near-Fault Simulated Records
      M. Askari Hasan Aghbarati
      Near-fault ground motions have caused very much damage in the vicinity of seismic sources during recent earthquakes. It is well known that under specific circumstances, intensive ground shakings near fault ruptures may be characterized by short-duration impulsive motion More
      Near-fault ground motions have caused very much damage in the vicinity of seismic sources during recent earthquakes. It is well known that under specific circumstances, intensive ground shakings near fault ruptures may be characterized by short-duration impulsive motions. This pulse-type motion is generally particular to the forward direction, where the fault rupture propagates towards the site at a velocity close to shear wave velocity. Ground motions affected by directivity focusing at near-field stations contain distinct pulses in acceleration, velocity and displacement histories. These ground motions can generate much higher base shears, inter-story drifts and roof displacements as compared to far-fault ground motions. Since structures under the effect of destructive earthquakes enter an inelastic phase, so the study of inelastic behavior of structures under the effect of such earthquakes seems to be important. This study examined maximum acceleration, velocity, displacement of the roof mass center, inter-story drifts and base shears of building in inelastic state at moment steel frame buildings designed on the basis of buildings design code against earthquake (2800 Standard, the third edition) under the near-fault records and the comparison of these parameters with the simulated ones. The results indicate that the maximum demand of drift of stories, acceleration, velocity, displacement of roof mass center and inelastic base shear and the way of hinge formation in non-linear state under the near-fault records is the same as simulated records in short buildings. Moreover, the more the height of structure becomes, the more different the behavior of structure becomes and the response is affected by more faults or errors. Manuscript profile
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      138 - The Effect of Recurring on Physical Properties of Concrete Containing Silica-Fume with Improper First Curing
      Ali Delnavaz Mohammad Reza Pezeshkian
      As regards if curing stops for some time and then resumes again, then strength gain will also stop and reactive, in this study with choose suitable curing conditions after improper first curing (recurring) for normal and silica-fume concrete, Effect of this curing condi More
      As regards if curing stops for some time and then resumes again, then strength gain will also stop and reactive, in this study with choose suitable curing conditions after improper first curing (recurring) for normal and silica-fume concrete, Effect of this curing conditions on strength and permeability was investigated. The results from tests such as compressive strength, capillary water absorption and water penetration under pressure, indicates that curing after 28 days for concretes with improper first curing, especially for silica-fume concretes could be effective and reduction permeability and increase compressive strength of concretes was observed Manuscript profile
    • Open Access Article

      139 - A Comparative Study on Seismic Performance of Hexagrid, Diagrid and Tubular Structural Systems
      Saeed Kia Darbandsari Maryam Firoozi NezamAbadi
      Hexagrid structural system is an innovated system with structural behavior which is similar to a tubular system. In this paper, a numerical study is conducted to estimate the seismic performance of horizontal hexagrid concerning the combined horizontal and vertical hexa More
      Hexagrid structural system is an innovated system with structural behavior which is similar to a tubular system. In this paper, a numerical study is conducted to estimate the seismic performance of horizontal hexagrid concerning the combined horizontal and vertical hexagrid, tubular and diagrid structural systems. First 30 and 50 story buildings are modeled using ETABS, then pushover and nonlinear dynamic analyses are performed on buildings using PERFORM 3D. Results indicate that the horizontal hexagrid system under nonlinear dynamic analysis has the least roof displacement; buildings capacity curves also demonstrate that the horizontal hexagrid is the most efficient system, as it brings lowest roof displacement along with high energy dissipation. Manuscript profile
    • Open Access Article

      140 - A Discrete Hybrid Teaching-Learning-Based Optimization algorithm for optimization of space trusses
      Siamak Talatahari Vahid Goodarzimehr
      In this study, to enhance the optimization process, especially in the structural engineering field two well-known algorithms are merged together in order to achieve an improved hybrid algorithm. These two algorithms are Teaching-Learning Based Optimization (TLBO) and Ha More
      In this study, to enhance the optimization process, especially in the structural engineering field two well-known algorithms are merged together in order to achieve an improved hybrid algorithm. These two algorithms are Teaching-Learning Based Optimization (TLBO) and Harmony Search (HS) which have been used by most researchers in varied fields of science. The hybridized algorithm is called A Discrete Hybrid Teaching-Learning Based Optimization (DHTLBO) that is applied to optimization of truss structures with discrete variables. This new method is consisted of two parts: in the first part the TLBO algorithm applied as conventional TLBO for local optimization, in the second stage the HS algorithm is applied to global optimization and exploring all the unknown places in the search space. The new hybrid algorithm is employed to minimize the total weight of structures. Therefore, the objective function consists of member’s weight, which is depends on the form of stress and deflection limits. To demonstrate the efficiency and robustness of this new algorithm several truss structures which are optimized by most researchers are presented and then their results are compared to other meta-heuristic algorithm and TLBO and HS standard algorithms. Manuscript profile
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      141 - Investigation of mechanical and durability properties of lightweight concrete containing Pumice
      Amirmohammad Soleimani Seyed Amir Hossein Hashemi
      In this research, the effect of the cement, sand, and pumice mixture on the durability of lightweight concrete is investigated. The intention of this paper is to replace a certain amount of the pumice percentage as an alternative option of the cement and pumice sand agg More
      In this research, the effect of the cement, sand, and pumice mixture on the durability of lightweight concrete is investigated. The intention of this paper is to replace a certain amount of the pumice percentage as an alternative option of the cement and pumice sand aggregate with conventional sand components. The experimental results include compressive strength, ion-chloride emission factor (RCPT and RCMT). The experiments are carried out at the concrete age of 28 and 90 days. The results indicate that pumice composition improves the durability of lightweight concrete. Furthermore, it was observed that the proposed mixing design have proper permeability resistance against the chloride ion attack. For 90 days aged concrete, it was notified that the samples had a chlorine ion penetration coefficient of 10% which is less than the concrete specimens of 28 days. Finally, the compressive strength of the new mixing design samples can beincreased by 1.5 to 2.5 Mpa after 90 days. Manuscript profile
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      142 - Estimation of Sloshing Wave Height in Broad Cylindrical Oil Storage Tanks Using Numerical Methods
      H Kazem S Mehrpouya
      Cylindrical steel tanks are important components of many industrial plants such as oil refineries and chemical plants. Usually failure of cylindrical tanks leads to serious consequences. During the past earthquakes such as 1964 Alaska and 1999 Turkey seismic performance More
      Cylindrical steel tanks are important components of many industrial plants such as oil refineries and chemical plants. Usually failure of cylindrical tanks leads to serious consequences. During the past earthquakes such as 1964 Alaska and 1999 Turkey seismic performance of cylindrical tanks revealed that tanks are seismically vulnerable. Therefore, evaluation of seismic performance of these structures is an important task in seismic prone areas. During an earthquake, a sloshing motion may occur in upper parts of the liquid. In storage tanks during earthquake if fluid wave height in tank increases, the fluid wave may damage the roof or some parts of roof holders. The tanks should resist against unfavourable impacts such as earthquakes. In this paper, 5 tanks with different H/D ratios in an oil refinery complex in Iran were studied using static and dynamical analysis (linear and non-linear). Spectrum and time history linear and non-linear analysis was completed in order to find the fluid wave height and also ratio of wave height to the tank diameter. Manuscript profile
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      143 - A Case Study of Performance Improvement of Femur Prosthesis
      Leila Shahryari Behtash JavidSharifi Mehdi Dabaghmanesh
      Nowadays, the placement of artificial prostheses in human skeleton, etc. is common due to different reasons such as fractures or deficiencies. Prostheses are structures that assist the performance of organs by reconstruction of some body parts through different methods More
      Nowadays, the placement of artificial prostheses in human skeleton, etc. is common due to different reasons such as fractures or deficiencies. Prostheses are structures that assist the performance of organs by reconstruction of some body parts through different methods to enable the organ to re-obtain its performance completely or partially and, since the use of external prostheses might lead to issues such as severe traumas, slow recovery and imposition of enormous hospital costs on the patient, therefore, use of internal prostheses can be an effective method for accelerating the process of improvement for the patient. By using CT-scan photos of a 54-year-old man weighing 60 kg and with a femur length of 36 centimeters, and also using a titanium prosthesis with diameters equaling 9 and 13 mm along with screws with diameters of 4 mm whose placement are with angles of ±4, ±4 and ±36 degrees, the geometry of the model has been provided and the model has been analyzed through the finite element method. Results indicated that in case of using the prosthesis with the diameter of 13 mm and screws of 4 mm with angle of +36, the least stress will be imposed on the bone and prosthesis. Manuscript profile
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      144 - Strength Characteristics of Clay Mixtures with Waste Materials in Freeze-Thaw Cycles
      Mahya Roustaei Mahmoud Ghazavi
      Waste tires, rubbers, plastic and steel materials, normally produced in every society, enter the environment and cause serious problems. These problems may, to some extent, be reduced by finding applications for them in engineering, for example, they can be used for geo More
      Waste tires, rubbers, plastic and steel materials, normally produced in every society, enter the environment and cause serious problems. These problems may, to some extent, be reduced by finding applications for them in engineering, for example, they can be used for geotechnical applications as backfill material and solving problems with low shear strength soils. Such materials may be subjected to freeze-thaw cycles, resulting in strength reduction. Freeze–thaw cycling is a weathering process which is normal in cold climates. In these cycles, thermodynamic conditions at temperatures below C cause translocation of water and ice which can change the engineering properties of soils. The present study investigates the effect of reinforcing soil with tire chips and steel fibers to reduce the effects of freeze-thaw cycles. To this aim, reinforced kaolinite clay was compacted in the laboratory and exposed to a maximum of 6 closed-system freeze-thaw cycles. The results of the study reveal that adding tires to clay prevents strength reduction due to freeze-thaw cycles. The soil samples which were mixed with 2% of steel fibers and 10% of tire chips were not affected by the freeze and thaw cycles as the pure samples were. These materials can reduce the effects of freeze and thaw cycles especially in cold regions. Manuscript profile
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      145 - A critical review on structure-soil-structure interaction
      Saeed Kia Darbandsari Ata Hojatkashani
      The purpose of this paper is to review computational methods in structure-soil-structure interaction. As a result of globalization, buildings are located close to each other. This issue happens especially in big cities, making the study of structure-soil-structure inter More
      The purpose of this paper is to review computational methods in structure-soil-structure interaction. As a result of globalization, buildings are located close to each other. This issue happens especially in big cities, making the study of structure-soil-structure interaction as an essential part of structural design process. The effect of soil medium, on which the building structure stands, especially on seismic behavior of building is well known. The effects of structures standing in a close distant to each other is the main issue in structure-soil-structure interactions. In this paper, analytical models of soil are reviewed. After a review on different analytical models of soil, the concepts and the computational efforts in the field of interaction between soil and adjacent buildings are discussed in order to provide the reader with the benefits and weaknesses of each concept. Different computer programs which suit structure-soil-structure interaction analysis and their main abilities are briefly reviewed as well. Manuscript profile
    • Open Access Article

      146 - Effect of Adding Nanoclay on the Mechanical Behaviour of Fine-grained Soil Reinforced with Polypropylene Fibers
      Alireza Tabarsa SeyedJassem Hosseini
      In this study the performance of clay nano-particles on the soil reinforced with Polypropylene fibers (PP-fiber) has been investigated. Also a series of investigations concerning the effect of random orientation of fibers on the engineering behaviour of soil were conduc More
      In this study the performance of clay nano-particles on the soil reinforced with Polypropylene fibers (PP-fiber) has been investigated. Also a series of investigations concerning the effect of random orientation of fibers on the engineering behaviour of soil were conducted. Soil mixtures were modified with varying percentages of nanoclay and Fibers. Unconfined compressive strength (UCS), Compaction, Atterberg limits, and microstructural (scanning electron microscopy) tests were conducted. In order to understand the micromechanical behaviour of nanoclay in fiber reinforced soil, the microstructure and morphology of fracture surfaces of samples were studied using Scanning Electron Microscopy (SEM). It was found that the addition of nanoclay significantly improves the performance of fiber reinforced soil in a unique way. This paper presents the understanding of nanoclaybehaviour and its impact on the overall mechanical characteristic and laboratory performance of fiber reinforced soil. Manuscript profile
    • Open Access Article

      147 - Cracks Analysis in Zavin Concrete Dam Using Fracture Mechanics Approach
      Hossein Rezaee Azariani Mohammad Reza Esfahani keivan bina Soheil Ghareh
      Most of the existing concrete dams are subjected to cracking. These cracks are caused by various factors such as construction practices, curing, loads and volume change of mass concrete which reduce the efficiency, failure or instability of concrete dams. Using fracture More
      Most of the existing concrete dams are subjected to cracking. These cracks are caused by various factors such as construction practices, curing, loads and volume change of mass concrete which reduce the efficiency, failure or instability of concrete dams. Using fracture mechanics as a new method to estimate stability and durability of concrete dams is recommended in scientific publications in worldwide. This study aimed to apply the principles and criteria of linear elastic fracture mechanics to evaluate the propagation of cracks in body and foundation of Kalat concrete gravity dam -that is located in the northern province of Khorasan Razavi, Iran- subjected to the worst-case loading, including the extraordinary loading case due to earthquake with full reservoir. For this purpose, ZENCRACK-v 7.7 and ABAQUS-v 6.10.1 software were utilized and nonlinear analysis of finite element are performed. Subsequently, linear elastic fracture mechanics criteria including stress intensity factor and maximum circumferential stress were calculated for existing cracks in various parts of dam body and foundation and stability of initial cracks, kinking angle and extension of them were determined. Based on the obtained results, crack propagation in areas near to both dam abutments is investigated. To do so, a plain strain condition is assumed that only expanded in longitudinal and transverse axes, but with being away from abutments toward dam center, crack growth logged from plain strain condition and expanded in the vertical direction. Also, under earthquake load with 10 second duration, maximum tension and compression stress were occurred between 2.32 to 4.26 seconds. Manuscript profile
    • Open Access Article

      148 - The Effect of Vertical Component of Earthquake on Continuous and Monolithic Frame Bridges
      A Delnavaz A Rahaee
      Performance of structures during recent earthquakes shows that the effect of vertical component of earthquake (VCE) could be considered as one of the main causes of bridges collapse. In most of bridge design codes, for seismic analysis of bridges, VCE is not taken into More
      Performance of structures during recent earthquakes shows that the effect of vertical component of earthquake (VCE) could be considered as one of the main causes of bridges collapse. In most of bridge design codes, for seismic analysis of bridges, VCE is not taken into account or a distinguished method isn’t presented for assessment of VCE. In the present work, the effect of VCE on two existing bridges, one with continuous deck and the other with monolithic frame system, was studied. The first model consisted of a pre-stress bridge in which the superstructure was connected rigidly to piers. The super structure consisted of 3 spans with length of 16, 48 and 16 m. The end of side slabs was put on abutments. The second model was a bridge with steel deck and concrete piers. The bridge superstructure was composed of I girder beams and in-place concrete slab. The beams were placed on 3 piers located 24 m far from each other, continually. In both models, the effect of VCE was studied considering the 3 acceleration of Tabas, Northridge and Kobe earthquakes and using linear and nonlinear time history and spectrum analysis on 3D models. In each analysis, the model was analyzed considering the 3 component and 2 horizontal components of earthquakes separately. The ratio of the difference of results in two analyses to the result of bridge response under its weight (DL) was compared. Through this method the amount of VCE effect on affected elements (according to statistical system of bridge) was found out. Manuscript profile
    • Open Access Article

      149 - Implementing Basic Displacement Function to Analyze Free Vibration Rotation of Non-Prismatic Euler-Bernoulli Beams
      Pouria Hajikarimi Reza Attarnejad
      Rotating beams have been considerably appealing to engineers and designers of complex structures i.e. aircraft’s propeller and windmill turbines. In this paper, a new flexibility-based method is proposed for the dynamic analysis of rotating non-prismatic Euler-Ber More
      Rotating beams have been considerably appealing to engineers and designers of complex structures i.e. aircraft’s propeller and windmill turbines. In this paper, a new flexibility-based method is proposed for the dynamic analysis of rotating non-prismatic Euler-Bernoulli beams. The flexibility basis of the method ensures the true satisfaction of equilibrium equations at any interior point of the elements. Following structural/mechanical principles, exact shape functions and consequently exact structural matrices i.e. consistent mass, geometric stiffness and flexural stiffness matrices are derived in terms of special so-called “Basic Displacement Functions”. The method is considered as the logical extension of conventional finite element method. Being straightforward formulated, the method can be incorporated into any standard finite element programs. The method poses no restrictions on either type of cross-section or variation of cross-sectional dimensions. The effects of rotational speed parameter and taper ratio on the variation of natural frequencies are studied and the results compare well with the other existing methods in the technical literature. Manuscript profile
    • Open Access Article

      150 - Exploring the Efficiency of Dampers for Repair and Strengthening of Existing Buildings
      F. Barati A. Esfandiari
      In this paper, seismic behavior of the existing buildings equipped by friction dampers is studied. Seismic performance of6-story, 9-story and 12-story steel buildings with damper and without damper were studied. The finite element modeling technique (SAP2000 Software) i More
      In this paper, seismic behavior of the existing buildings equipped by friction dampers is studied. Seismic performance of6-story, 9-story and 12-story steel buildings with damper and without damper were studied. The finite element modeling technique (SAP2000 Software) is used for analysis. Time History analyzing was done to achieve this purpose. For nonlinear dynamic analysis, the responses of the structures to three earthquake records (Tabas, Naghan, and artificial waveform) were obtained. A series of analyses were made to determine the optimum slip load of the friction dampers to achieve minimum response. Also, in order to evaluate the performance of the friction dampers in asymmetric structures, an asymmetric structure was utilized. The obtained results show significant improvement of seismic behavior and efficiency of the friction damper for seismic retrofitting to these buildings. Manuscript profile
    • Open Access Article

      151 - Designing a prefabricated sandwich composite roofing system Made up of resisting facings and light-weight concrete core with truss-shaped connectors
      Arash Totonchi Allah dad Ahmadi
      In this paper, a new roofing system is introduced, which is constructued using the precast composite sandwich panels. This roofing sandwich panels system consists of three kinds of precast concrete sandwich panels including capital panels, beam or between columns panels More
      In this paper, a new roofing system is introduced, which is constructued using the precast composite sandwich panels. This roofing sandwich panels system consists of three kinds of precast concrete sandwich panels including capital panels, beam or between columns panels, and slab or middle panels. The panels are composed of three layers; A high strength reinforced concrete top layer. A thick layer of light-weight concrete as the intermediate layer or core. And a tensile resistant reinforced concrete bottom layer. The panels are connected together by special connectors at the edges.In this research, the influence of shear connector stiffness is studied which is measured according to their diameter on ultimate resistant and combined performance of the panels. The results of finite element analysis by ABAQUS software show a logical behavior of load-deflectioncurves in shear connectors. Based on the economic and weight comparisons the dead and live loads,the proposed sandwich panel roofing is approximately 44 percent lighter than the conventional steel joist and concrete blocks. This comparison shows the superiority of this roofing system to joists and concrete blocks system and seems to be a good alternative for it. Due to the possibility of prefabrication and industrial production of the panels under factory conditions, and various other technical, economic, and constructional advantages of this roofing system, it is concluded that it can be viable substitute for current roofing systems in low to high-rise buildings and can save a considerable amount of material, labor, time, and cost in building construction. Manuscript profile
    • Open Access Article

      152 - Effects of Glass Fiber Reinforced Polymer on Geotechnical Properties of Clayey Soil
      Fardin Asadollahi Rouzbeh Dabiri
      Soil reinforcement can be considered as the combination of two parts. One part is soil for compressive stress capacity and another part is some material such as geosynthetics such as steel belts and fibers for tensile stress capacity. Soil improvement is one of the usef More
      Soil reinforcement can be considered as the combination of two parts. One part is soil for compressive stress capacity and another part is some material such as geosynthetics such as steel belts and fibers for tensile stress capacity. Soil improvement is one of the useful methods to increase the strength parameters of the soil. The main goal of this study is to evaluate the effects of GFRP on the bearing capacity, shear strength, and permeability of clayey soil. For this purpose, the length of GFRP is selected 10 mm and amount of GFRP are 0.2, 0.4, 0.6, 0.8 and 1% that mixed randomly with clay. Mixture specimens prepared using the optimum water content. Bearing capacity of specimens measured by unconfined compressive test and direct shear test. Also, Permeability parameter assessed based on the falling head permeability test. Results of this study showed that with mixing GFRP up to 0.8% increases the clay bearing capacity and flexibility. Although with continuing to add GFRP the bearing capacity decrease, the clay permeability using GFRP is increased. Manuscript profile
    • Open Access Article

      153 - Effect of column-foundation connection stiffness on seismic performance of rocking steel braced frame
      Masoumeh Farshbaf Abdolreza S. Moghadam
      Residual drifts after severe earthquakes interrupt serviceability of buildings. Retrofitting of such buildings is in many cases very difficult and consumes lots of time and money. Recently, there are some attempts to develop the seismic design procedures to not only sat More
      Residual drifts after severe earthquakes interrupt serviceability of buildings. Retrofitting of such buildings is in many cases very difficult and consumes lots of time and money. Recently, there are some attempts to develop the seismic design procedures to not only satisfy life safety criteria but also lead to more economical buildings. One of these modern methods of improving seismic performance of the steel structures is using systems with ability of rocking. The main features of these new systems are to concentrate the damages in specific easily repairable locations of structures, to dissipate more energy and to reduce and limit the residual deformations. In this paper the effects of the column-foundation connection stiffness on the seismic performance of rocking steel braced frame are studied. Nonlinear dynamic time history analyses are applied, using seven far-field ground motion records in two intensity levels. The response parameters are mean of the maximum vertical accelerations of rocking columns, drifts, performance levels, in addition of the positive and negative vertical displacements. The results of this study indicate the positive effect of increase in the tensile stiffness and decrease of compressive stiffness in the column base connection on vertical accelerations, uplift and performance levels in the models with viscous dampers. Manuscript profile
    • Open Access Article

      154 - Analysis of Masonry Infill Panels Retrofitted with FRP Sheets in R/C Frames
      Hosein Parastesh Murat Saatcioglu
      Masonry infill walls are often used as non-structural elements. According to the past structural failure, ignorance of interaction between infill walls and enclosed frame may lead to the different seismic response for non-ductile building frames. The main contribution o More
      Masonry infill walls are often used as non-structural elements. According to the past structural failure, ignorance of interaction between infill walls and enclosed frame may lead to the different seismic response for non-ductile building frames. The main contribution of this paper is to analytically investigate the behavior of reinforced concrete with masonry infill panels as participating structural. In doing so, a finite element model based on an equivalent strut method is conducted to represent the behavior of masonry panels. The strut model is calibrated using the results of the companion experimental program, which examined the cyclic behavior of infill panels with and without FRP sheets. Accordingly, a nonlinear spring element and a shell element are used to simulate the behavior of masonry strut elements and FRP sheets, respectively. The nonlinear static analysis (Push over analysis) is accomplished using SAP2000 [1] structural analysis software for a 10-story building with FRP sheets subjec Manuscript profile
    • Open Access Article

      155 - Assessment of an RC existing hospital building with special moment frame using fragility curve
      Farhad Cheraghi Abdolreza S. Moghadam
      In this study, an existing hospital structure has been evaluated with incremental dynamic analysis (IDA). This building is accommodated in Karaj with soil type II. At first, two 2-D frames along X, Y direction are selected. Then, five performance levels are determined a More
      In this study, an existing hospital structure has been evaluated with incremental dynamic analysis (IDA). This building is accommodated in Karaj with soil type II. At first, two 2-D frames along X, Y direction are selected. Then, five performance levels are determined according to “Rehabilitation Code for Existing Buildings (Publication No. 360) including Immediate Operational (IO), Limited Damage (LD), Life Safety (LS), Limited Life Safety (LLS), and Collapse Prevention (CP). The Peak Ground Acceleration (PGA) as earthquake intensity and relative displacement (Drift) as the failure index has been used for incremental dynamic analysis method via seismo-struct software. In the next step, the probability of reaching or exceeding of the structure to a limit state was determined. Results of incremental dynamic analysis for fragility curves show that the probability of reaching or exceeding from IO level is approximately . This probability is almost for LD, for LS, for LLS, and for CP. It has been signified that the probability of fragility is raised with increasing in PGA Manuscript profile
    • Open Access Article

      156 - The possible use of Sewage Sludge Ash (SSA) in Self-Consolidating Concrete (SCC) for environmental sustainability
      Mohamadreza Khanban Mahdi Mahdikhani
      Nowadays, waste production is increased due to the growth of technology and excessive use of natural resources as well as production of new chemicals, among which the hazardous wastes are no exception of that stabilization and solidification method is one of the hazardo More
      Nowadays, waste production is increased due to the growth of technology and excessive use of natural resources as well as production of new chemicals, among which the hazardous wastes are no exception of that stabilization and solidification method is one of the hazardous waste management methods through which the waste materials are stabilized and confined. High flexibility for various pollutant compounds, ease of use, and being economical for large volumes of waste has led researchers to use this method to treat various wastes. In this research, sludge ash from sewage treatment plantsuses as waste in order to perform the stabilization and solidification process. Nine mix designs with a water to cement ratio of 0.46; and 0, 6, and 10 percent dried sludge residue of the Alborz Industrial City in Qazvin as the replacement of fine aggregate; 0, 2, and 4 percent of silica fume; and cement content of 600 kg/m3are produced. The mini slump flow, mini V-funnel, compressive strength, electrical resistancetests were carried out on the solidified samples to investigate the effect of waste on the performance of the mortar.The results show that the use of this waste as a substitute for fine aggregate could be taken into consideration. Manuscript profile

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