Research On The Aseismic Behavior Of Shear Wall Coupling Beams With Different Reinforcement Layouts

Shear walls are commonly used in high-rise buildings in order to resist lateral loads. Due to the presence of regular door or window openings, a shear wall is often divided into smaller wall units coupled together by coupling beams. Earthquake resistance performance of shear walls depends greatly on the load capacity, ductility and energy dissipation of coupling beams. Conventional design and layout of reinforcement in coupling beams with small span-to-depth ratio doesn't meet the demands of shear resistance and ductility, so the need of a new reinforcement layout which can provide an optimal earthquake resistance performance is of vital importance.The present work uses a finite element method to investigate the aseismic performance of shear-wall coupling-beam with 4 kinds of reinforcement layouts: conventional (standard), simple diagonal, rhombic, and diagonal with transversal ties. In finite element study, all coupling beams have a span-depth ratio of 1.25 and width of 180mm. The comparison analysis about load-deformation, stiffness, crack propagation, stress distributions, load-bearing capacity, and ductility is presented. The results show that the rhombic layout showed superiority in terms of ductility and shear-bearing capacity.An 18-story building is then selected as the case study to investigate the aseismic performance of shear wall with standard and rhombic layout coupling beams under monotonic loading. Numerical results show that the shear wall with rhombic layout coupling beam has a 44% higher shear resistance,51% higher roof displacement and a 97% higher ductility factor compared to that of shear wall with standard layout coupling beam. The optimal seismic performance in terms of shear resistance and ductility, simplicity of detailing, makes the rhombic layout coupling beam an attractive choice.