Verification of Seismic Response Modification Factors of Uncoupled Composite Plate Shear Walls/Concrete Filled

Abstract

In this paper, the seismic design factors for uncoupled composite plate shear walls/concrete filled (C-PSW/CF), a.k.a. SpeedCore, are verified by conducting a study using FEMA methodology. These are the seismic response modification factor, R, the deflection amplification factor, Cd, and the overstrength factor, Ωo; and their values for C-PSW/CF are specified as 6.5, 5.5, and 2.5, respectively. A study was needed, as these factors for uncoupled C-PSW/CFs, included in ASCE 7 since as far back as its 2000 edition, were chosen solely based on the seismic performance of similar structural systems and engineering judgment of the committee members. For this study, four archetypes with planar walls and three archetypes with C-shaped C-PSW/CF walls were chosen. Two different damage measures (DM) were chosen for this study; namely, 3% and 5% maximum interstory drifts. Based on FEMA methodology, all archetypes satisfied the specified performance requirement considering a “good” rating for total system collapse uncertainty (βTOT).