This paper deals with the irregular profile of braced steel frame building in vertical direction with shear link bracing systems.The underlying fact of the paper is the effect of seismic force in braced frames with di...This paper deals with the irregular profile of braced steel frame building in vertical direction with shear link bracing systems.The underlying fact of the paper is the effect of seismic force in braced frames with different types of irregularities including mass irregularity,mass discontinuity and overhanging mass.For each successive model,the position of shear link bracings has been fixed to make the study effective.This study has investigated the vulnerable effect of irregular profiles in steel frame buildings.To attain the behavior of each frame,linear time history analysis method has been adopted for the present study.FEMA356 standard has been used here for linear time history analysis.Investigations on different frames exhibit that regular profile with symmetry in mass is more efficient while using overhanging mass is detrimental considering the time dependent displacements and accelerations.展开更多
This study presents the micro-scale behavior of granular materials under biaxial cyclic loading for differ- ent confining pressures using the two-dimensional （2D） discrete element method （DEM）. Initially, 8450 ova...This study presents the micro-scale behavior of granular materials under biaxial cyclic loading for differ- ent confining pressures using the two-dimensional （2D） discrete element method （DEM）. Initially, 8450 ovals were generated in a rectangular frame without any overlap. Four dense samples having confining pressures of 15, 25, 50, and 100 kPa were prepared from the initially generated sparse sample. Numeri- cal simulations were performed under biaxial cyclic loading using these isotropically compressed dense samples. The numerical results depict stress-strain-dilatancy behavior that was similar to that observed in experimental studies. The relationship between the stress ratio and dilatancy rate is almost indepen- dent of confining pressures during loading but significantly dependent on the confining pressures during unloading. The evolution of the coordination number, effective coordination number and slip coordina- tion number depends on both the confining pressures and cyclic loading. The cyclic loading significantly affects the microtopology of the granular assembly. The contact fabric and the fabric-related anisotropy are reported, as well. A strong correlation between the stress ratio and the fabric related to contact normals is observed during cyclic loading, irrespective of confining pressures.展开更多
文摘This paper deals with the irregular profile of braced steel frame building in vertical direction with shear link bracing systems.The underlying fact of the paper is the effect of seismic force in braced frames with different types of irregularities including mass irregularity,mass discontinuity and overhanging mass.For each successive model,the position of shear link bracings has been fixed to make the study effective.This study has investigated the vulnerable effect of irregular profiles in steel frame buildings.To attain the behavior of each frame,linear time history analysis method has been adopted for the present study.FEMA356 standard has been used here for linear time history analysis.Investigations on different frames exhibit that regular profile with symmetry in mass is more efficient while using overhanging mass is detrimental considering the time dependent displacements and accelerations.
文摘This study presents the micro-scale behavior of granular materials under biaxial cyclic loading for differ- ent confining pressures using the two-dimensional （2D） discrete element method （DEM）. Initially, 8450 ovals were generated in a rectangular frame without any overlap. Four dense samples having confining pressures of 15, 25, 50, and 100 kPa were prepared from the initially generated sparse sample. Numeri- cal simulations were performed under biaxial cyclic loading using these isotropically compressed dense samples. The numerical results depict stress-strain-dilatancy behavior that was similar to that observed in experimental studies. The relationship between the stress ratio and dilatancy rate is almost indepen- dent of confining pressures during loading but significantly dependent on the confining pressures during unloading. The evolution of the coordination number, effective coordination number and slip coordina- tion number depends on both the confining pressures and cyclic loading. The cyclic loading significantly affects the microtopology of the granular assembly. The contact fabric and the fabric-related anisotropy are reported, as well. A strong correlation between the stress ratio and the fabric related to contact normals is observed during cyclic loading, irrespective of confining pressures.
