List of Articles

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  1 - Design Approach of Bolts and Sandwiching Steel Plates in Hybrid-Sandwiching Systems Based on FEM
  Alireza Zaferani Pasha Javadi Parham Memarzadeh
  Conventional reduced beam sections (RBS) maintain their capacity with up to 4% drift angle, after which local buckling at the reduced section significantly reduces their resistance. The use of hybrid-sandwiched reduced beam sections (HS-RBS) in the reduced section of co More

  Conventional reduced beam sections (RBS) maintain their capacity with up to 4% drift angle, after which local buckling at the reduced section significantly reduces their resistance. The use of hybrid-sandwiched reduced beam sections (HS-RBS) in the reduced section of conventional RBS beams previously proposed by the authors can increase the energy absorption capacity, allowing the beam to reach 7% drift without losing capacity. The experimental results indicate that placing the HS-RBS in the reduced section of the RBS beam does not disrupt its main role in forming a plastic joint in the reduced section. HS-RBS is comprised of grout, nuts and bolts, and the sandwiching plates. In this system, the bolts and the sandwiching plate enclose the grout and the bolts are placed in the grout on two sides of the beam web in the reduced section to increase the grout's capacity to resist the tensile stresses arising from the web buckling. The sandwiching plate is located in the reduced section on two sides of the flange to enclose the grout and increase the buckling resistance of the flange. This study employed finite element modeling (FEM) to analyse beam bolts with different diameters for different sections of the HS-RBS to obtain the best diameter for each bolt. Moreover, sandwiching plates with different thicknesses were examined to find the best thickness. Manuscript profile
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  2 - Seismic Fragility Analysis of a RC Bridge with Uniform and Non-Uniform Random Scour Patterns
  Ali Raoof Mehrpour Hosseini Mehran Seyedrazzaghi Nasser Shamskia
  Previous natural disaster assessments had identified bridges as vulnerable structures against hydraulic hazards, particularly scouring. Additionally, in areas with high seismic activity, bridges are exposed to minor damage to complete collapse, in most cases requiring i More

  Previous natural disaster assessments had identified bridges as vulnerable structures against hydraulic hazards, particularly scouring. Additionally, in areas with high seismic activity, bridges are exposed to minor damage to complete collapse, in most cases requiring immediate occupancy structural performance levels in the event of an earthquake. Previous studies have focused on vulnerability assessments by considering the effects of simultaneous hazards. This study examines a simply supported RC bridge model with a discontinuous deck-girder superstructure installed on cap beams via elastomers. Seismic vulnerability assessments were conducted by developing fragility curves through nonlinear time history analyses on scoured models. One of the study's objectives is to consider the effects of non-uniform patterns in different foundations of the four-span model by generating random depth samples. The study also evaluated even depths as the uniform scenario for vulnerability assessment. The results indicate that, in all limit states considered in the study, the uniform has a higher probability of exceeding the limit states than the non-uniform scenario. However, in evaluating critical scoured models, the uniformly maximum credible scoured pattern did not necessarily have a higher probability of exceeding all limit states. In other words, the non-uniform scenario, which had pier(s) with the maximum credible scour depth, had a more critical vulnerability in some limit states. Manuscript profile
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  3 - Multi-Objective Optimization of the Depth and Cementation of Liquefiable Soil Surrounding Tunnels
  Mohammad Shabani Soltan Moradi Mohammad Azadi Homayoun Jahanian
  Designing tunnels in liquefiable sandy soils presents a significant challenge in determining the optimal depth and extent of soil cementation around them. Reducing the depth of the tunnel decreases both the bending anchor force and the axial load on the tunnel's shell, More

  Designing tunnels in liquefiable sandy soils presents a significant challenge in determining the optimal depth and extent of soil cementation around them. Reducing the depth of the tunnel decreases both the bending anchor force and the axial load on the tunnel's shell, yet it leads to an increase in ground surface settlement, and the opposite is true when depth is increased. Enhancing the cementation level at the tunnel's optimal depth reduces both structural uplift and shear forces exerted on the tunnel lining, but it also leads to an increase in axial loads and vice versa. Given the contradictory nature of these outcomes, the FLAC software was employed to simulate tunnels in liquefiable soils to address this dilemma. Subsequently, a neural network was utilized to identify correlations between the inputs and outputs of the simulation. This network was the objective function for identifying optimal values by applying a genetic algorithm. Optimal design parameters were derived using the NSGA-II modified algorithm, a multi-objective optimization technique based on the objective functions. Ultimately, Pareto charts generated from the multi-objective optimization process enabled designers to select the most suitable tunnel location according to their specific requirements concerning depth and soil cementation in liquefied soils. Manuscript profile
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  4 - Optimization of surficial settlement originated from the excavation of twin tunnels on surface structures with finite dimensions
  Hesam Pourhabiby Masuleh
  In urban regions, the stability and safety of surface structures are essential. With the development of cities and increasing building density in metropolitan areas, the construction of underground structures like subway tunnels will be considered more and more. The tun More

  In urban regions, the stability and safety of surface structures are essential. With the development of cities and increasing building density in metropolitan areas, the construction of underground structures like subway tunnels will be considered more and more. The tunnels are located close to the ground surface in most urban regions. Therefore, excavating these tunnels causes some displacements in the soils around the tunnels, leading to some adverse effects on the surface structures. Predicting deformations looks essential to reducing these effects, showing the importance of tunnel and structure interaction. In this paper, using three-dimensional numerical simulation and parametric studies, the effect of various parameters on the displacement of tunnels and their adjacent buildings are studied. The optimum surface settlement values are predicted using the neural network and developed optimization algorithms. The parameters under study are composed of: the horizontal distance between tunnels, the depth of tunnels, the angle between tunnels, the excavation distance between two tunnels, the diameter of the tunnels, tunnels' contraction, the soil's internal friction angle, and the soil's cohesion. Using a neural network and optimization algorithms can considerably help optimize the design and significantly reduce adverse effects on the surface structures during the tunnel excavation. The results from the neural network showed that the optimum state of displacement happens when the soil's cohesion, tunnels' contraction, diameter, and depth are the minimum values, and the excavation distance between two tunnels is the maximum value. Manuscript profile
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  5 - Effect of Pile Cap Geometry on Soil Arching Behavior in GRPS Embankments: A Comparative Study
  mohammad amir mirzaei Monireh Karimian Mobarakeh Arif Khan Adriko norman burua rashid hajivand dastgerdi
  This comprehensive study in geotechnical engineering presents valuable insights and advancements in the field of Geosynthetic-Reinforced Pile-Supported Embankments (GRPS). The study focuses on the analysis of pile caps in GRPS using three-dimensional finite element mode More

  This comprehensive study in geotechnical engineering presents valuable insights and advancements in the field of Geosynthetic-Reinforced Pile-Supported Embankments (GRPS). The study focuses on the analysis of pile caps in GRPS using three-dimensional finite element modeling, specifically employing PLAXIS-3D software. The research investigates the effects of different pile head shapes on soil arching, settlement, and stress distribution, emphasizing the significance of pile head selection for enhancing soil arching and reducing ground settlement. The study recommends larger pile heads with flattened top surfaces, as demonstrated in sections 4 and 5, as optimal choices for pile head design in GRPS projects. The proposed analytical model captures the time-dependent settlement behavior of subsoils, but a slight underestimation of settlement after embankment construction suggests the need for further consideration of factors like pile settlement and bottom sandy silt settlement. Future research should refine the analytical model to improve settlement predictions by incorporating these factors. Additionally, the study highlights the importance of investigating GRPS embankments with floating piles, complex construction processes, water effects on soil arching, and embankment performance. It is noted that earthquake loading was not specifically addressed, indicating the need for comprehensive research in this area. Overall, this study contributes to the knowledge of GRPS embankments and provides recommendations for design, construction, and future research directions. Manuscript profile
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  6 - Location of municipal landfills Analytical Hierarchy process (AHP) In GIS environment (Case study of Qazvin city)
  Mojtaba Ebrahim beiki keshmarzi
  Solid waste is an integral part of human life and the production of its types in different quantities and qualities is one of the most important environmental problems of the present age. To prevent environmental pollution in the community, waste must be disposed of hyg More

  Solid waste is an integral part of human life and the production of its types in different quantities and qualities is one of the most important environmental problems of the present age. To prevent environmental pollution in the community, waste must be disposed of hygienically and engineeringly. One of the methods of waste disposal is engineering waste disposal method. In this study, our emphasis is on the impact of ecological factors on the location of urban solid waste landfills in Qazvin city using spatial analysis in GIS environment for optimal location of municipal landfills. For this purpose, the required digital data was collected and then transferred to the ArcGIS environment. After creating the database, multi-criteria analytical decision-making models were implemented, the reliable method of AHP hierarchical analysis. As a result, by using the AHP method, hierarchical criteria have been used to locate a suitable sanitary place for landfilling of generated waste in Qazon city, and the most optimal place has been selected from 4 proposed places for sanitary landfilling of waste. Manuscript profile