List of Articles concentrically braced frame

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  1 - Evaluation of Steel Braced Frames under Vertical and Horizontal Components of Near Field Earthquake
  علی گل افشار متین روشنی محمد حسین ثقفی
  In the common practice design of structures, Often the effect of vertical component of earthquake is ignored, but this component is important parameter especially in near field Earthquakes. The objective of this paper is study the effect of vertical and horizontal compo More

  In the common practice design of structures, Often the effect of vertical component of earthquake is ignored, but this component is important parameter especially in near field Earthquakes. The objective of this paper is study the effect of vertical and horizontal component of earthquake ground motion in steel braced frames. First verification of numerical models through finite element software package (ABAQUS) is carried out. Comparison of the result of load displacement curve for numerical and experimental model shows matching result. After this, two concentrically braced frames with X-configuration are selected from previous researches. Four earthquake records have been used for this study. Kobe, Northridge, Tabas and Imperial Valley. Two components of earthquake are applied simultaneously to frames under nonlinear time history analysis. The results that extract from the analysis content of vertical and horizontal displacement of roof and plastic dissipated energy during earthquakes. the intensity of the former parameters is depend of earthquake intensity and frequency content of them. Assessing the result reveal that in the three story frame, the ratio of maximum vertical displacement to maximum horizontal displacement is crucial parameter with respect to seven story braced frame. Also the time of plastic energy dissipated for frames is short because of nature of near field earthquake. Manuscript profile
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  2 - Advanced Analysis of Concentrically Braced Frames (CBFs) by Energy Approach
  mohsen izadinia Armin Pouya Parham Memarzadeh
  Advanced analysis refers to the method which the strength and stability of the system and structural members are determined in an integrated manner and there is no need to check separately each member. This approach makes structural designers better understand the main More

  Advanced analysis refers to the method which the strength and stability of the system and structural members are determined in an integrated manner and there is no need to check separately each member. This approach makes structural designers better understand the main characteristics affecting the actual behavior of structures. certainly, one of the most widely used structural systems in the construction industry is Concentrically braced frames (CBFs). Mainly, these kinds of frames collapse because of soft story formation at one or a few stories in which excessive brace buckling occurs. This study provides an intuitive understanding of the collapse mechanism of CBFs with 3-18 stories subjected to mainshock-aftershock sequences. Such understanding will support development of design methods that preclude low-capacity collapse modes specially under multi-shock excitations. This paper assesses the collapse mechanism as a stage in which the imposed seismic energy fails to dissipate and eventually leads to uncontrolled kinetic energy in structure. The investigation focuses on the role and distribution of the various energy measures and different dissipating mechanisms throughout the structures. Collapse mechanism is identified for various combinations of the utilized mainshock-aftershock pairs that are gradually scaled following the IDA process. The distribution of input and dissipated energies along various stories reveals the role of upper stories in damping the imposed energy. Furthermore, the similarity between the height profile of the residual drifts and the story imposed energies highlights the characteristic of the structures in adapting their drift response to a mode with the highest energy absorption. Manuscript profile
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  3 - Advanced Analysis of Concentrically Braced Frames (CBFs) by Energy Approach
  Armin Pouya mohsen izadinia Parham memarzadeh,
  10.30495/civil.2024.709617
  Advanced analysis refers to a method in which the strength and stability of the system and structural members are recognized in an integrated manner and there is no need to separately check the capacity of the structural members. This approach is a suitable method for e More

  Advanced analysis refers to a method in which the strength and stability of the system and structural members are recognized in an integrated manner and there is no need to separately check the capacity of the structural members. This approach is a suitable method for evaluating the real behavior of structures and makes structural designers better understand the main characteristics affecting the actual behavior of structures. Undoubtedly, one of the most widely used structural systems in the construction industry is Concentrically braced frames (CBFs). Mainly, these kinds of frames collapse because of a soft story formation in one or more stories in which excessive brace buckling occurs. Using second order inelastic analysis, this study provides an intuitive understanding of the collapse mechanism of CBFs with 6 and 18 stories subjected to mainshock-aftershock sequences. Such understanding will support development of design methods that preclude low-capacity collapse modes specially under multi-shock excitations. This paper assesses the collapse mechanism as a stage in which the imposed seismic energy fails to dissipate and eventually leads to uncontrolled kinetic energy in structure. The investigation focuses on the role and distribution of the various energy measures and different dissipating mechanisms throughout the structures. Collapse mechanism is identified for various combinations of the utilized 32 mainshock-aftershock pairs that are gradually scaled following the incremental dynamic analysis (IDA) process. The distribution of input and dissipated energies along various stories reveals the role of upper stories in damping the imposed energy. Furthermore, the similarity between the height profile of the residual drifts and the story imposed energies highlights the characteristics of the structures in adapting their drift response to a mode with the highest energy absorption. Manuscript profile
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  4 - Evaluation of the Seismic Performance of Rocking Motions and its Effects on the Controlling Provisions of Special Steel Moment-resisting‎ Systems Dual with CBF Bracing
  Ali Parvari Ehsan Azizi
  In this study, 4-, 8-, and 12-Story steel special concentrically braced frame (SCBFs) structures were considered in area with high seismically hazard and soil type II according to Iranian's 2800 code provision. Structures are residential use and have regularity in plane More

  In this study, 4-, 8-, and 12-Story steel special concentrically braced frame (SCBFs) structures were considered in area with high seismically hazard and soil type II according to Iranian's 2800 code provision. Structures are residential use and have regularity in plane and vertical distribution. Structures were modeled using Sap 2000 software to investigate the effect of self-centering ‎motion under seven near-field earthquakes. All models assumed with and without dual system controlling provisions. The results of this research indicate that without dual system provisions, considering the self-centering ‎motion in ‎4-, 8-, and 12-Story SCBFs‎ reduces base shear of structures in contrast with increasing deformation of top floor and column axial force. In average, the self-centering ‎motion‎ dissipate energy more than fixed base one. With controlling dual system provisions, considering the self-centering ‎motion in ‎4-, 8-, and 12-Story ‎SCBFs‎ reduces base shear of structures, whereas increases deformation of top floor ‎and column axial force. Moreover, in this case of study, energy dissipation are more than with controlling ‎one. Considering the self-centering ‎motion in ‎8-, and 12-Story ‎SCBFs‎ reduces base shear of ‎structures and top floor deformations, meanwhile column axial force‎ was increased. It can be seen that in ‎4-, and 12-Story ‎SCBFs considering code provisions had a better results, whereas in ‎8-Story ‎SCBFs ‎neglecting code provisions was accepted. Manuscript profile
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  5 - Evaluation the Performance and Seismic Comparison of Steel Moment Dual Systems in Rocking Frames with CBF and EBF Bracing
  Ali Parvari Arman Beglar
  In recent years, considering vertical movement in structures, which is known as self-centering motion, is one of the methods used to dissipate the earthquake energy. In this study, 4-, 8-, and 12-Story steel structures with special concentrically braced frame (SCBFs) an More

  In recent years, considering vertical movement in structures, which is known as self-centering motion, is one of the methods used to dissipate the earthquake energy. In this study, 4-, 8-, and 12-Story steel structures with special concentrically braced frame (SCBFs) and eccentrically braced frames ‎(SEBFs) ‎were considered in order to investigate the effect of self-centering ‎motion under seven near-field earthquakes using Sap 2000 software. The results of this research indicate that considering the self-centering ‎motion, the behavior of structures are changing in SCBFs and SEBFs. In ‎, 4-, 8-, and 12-Story SEBFs structures with considering the self-centering ‎motion, the column and bracing ‎forces were increased which this was different with SCBFs ‎ structures. Considering the self-centering ‎motion, more plastic joints are formed in the beams. Therefore, in the self-centering ‎of the columns, the beams outside the bay are more affected. In general, the results indicate that the self-centering ‎motion is better in the SCBFs. Manuscript profile
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  6 - Advanced Analysis of Concentrically Braced Frames (CBFs) by Energy Approach
  Armin Pouya mohsen izadinia Parham Memarzadeh
  10.30495/civil.2023.701247
  Advanced analysis refers to a method in which the strength and stability of the system and structural members are recognized in an integrated manner and there is no need to separately check the capacity of the structural members. This approach is a suitable method for e More

  Advanced analysis refers to a method in which the strength and stability of the system and structural members are recognized in an integrated manner and there is no need to separately check the capacity of the structural members. This approach is a suitable method for evaluating the real behavior of structures and makes structural designers better understand the main characteristics affecting the actual behavior of structures. Undoubtedly, one of the most widely used structural systems in the construction industry is Concentrically braced frames (CBFs). Mainly, these kinds of frames collapse because of a soft story formation in one or more stories in which excessive brace buckling occurs. Using second order inelastic analysis, this study provides an intuitive understanding of the collapse mechanism of CBFs with 6 and 18 stories subjected to mainshock-aftershock sequences. Such understanding will support development of design methods that preclude low-capacity collapse modes specially under multi-shock excitations. This paper assesses the collapse mechanism as a stage in which the imposed seismic energy fails to dissipate and eventually leads to uncontrolled kinetic energy in structure. The investigation focuses on the role and distribution of the various energy measures and different dissipating mechanisms throughout the structures. Collapse mechanism is identified for various combinations of the utilized 32 mainshock-aftershock pairs that are gradually scaled following the incremental dynamic analysis (IDA) process. The distribution of input and dissipated energies along various stories reveals the role of upper stories in damping the imposed energy. Furthermore, the similarity between the height profile of the residual drifts and the story imposed energies highlights the characteristics of the structures in adapting their drift response to a mode with the highest energy absorption Manuscript profile