Seismic performance of steel plate shear walls considering various design approaches

Research was conducted to investigate the seismic performance of steel plate shear walls (SPSWs) designed by different philosophies. First, analytical study was conducted to investigate impact of formation of in-span plastic hinges on horizontal boundary elements (HBEs) on the seismic behavior of SPSWs. The development of in-span plastic hinges has significant consequences on the behavior of SPSWs, namely: lower lateral strength due to partial yielding of the infill plates and significant plastic incremental deformations on the HBEs than can reach total HBE rotations greatly exceeding 0.03 radians when the structure was pushed cyclically up to a maximum lateral drift of 3%. Second, collapse assessment of steel plate shear walls with various structural configurations (e.g., panel aspect ratio, seismic weight intensity, and number of story) was conducted to investigate impact of sharing of story shear forces between the boundary frames and infill plates on the performance of SPSWs. The FEMA P695 methodology was used for this purpose. SPSWs designed with the current seismic performance factors specified in the ASCE 7-10 (i.e., R, Ω_o, and C_d factors are 7, 2, and 6, respectively) and neglecting the contribution of their boundary moment resisting frames to resist story shear forces met the FEMA P695 performance criterion while that was not the case for SPSWs designed considering the sharing of story shear forces between the boundary frame and infill plates. Adjusted seismic performance factors (i.e., R, Ω_o, and C_d factors are 5, 1, and 5, respectively) were required for the latter SPSWs to rigorously meet the FEMA P695 performance criteria.