Seismic design parameters (R, C_d, and Ω₀) for uncoupled composite plate shear walls−concrete filled (C‐PSW/CF)

Abstract

Composite Plate Shear Walls−Concrete Filled (C-PSW/CF) are an innovative seismic force resisting system recently adapted for building applications. The walls consist of parallel steel faceplates connected with tie bars and filled with concrete. This paper summarizes the results of a recent FEMA P695 study completed to verify seismic design parameters for uncoupled C-PSW/CFs with rectangular flange plate boundary elements. Seven archetype structures were: (i) designed, (ii) modeled using a benchmarked fiber-based finite element analysis approach, (iii) subjected to nonlinear pushover analysis, (iv) and to incremental nonlinear dynamic analysis to failure for 22-sets of scaled ground motions, and (v) the results were statistically analyzed to assess performance. These structures ranged from three (3) to twenty-two ( 22) stories and included both planar and C-shaped configurations. As part of this design process, recommendations for stiffness approximations for linear analysis of C-PSW/CFs were developed. Additionally, these nonlinear incremental dynamic analysis results were postprocessed to determine the rotation and strain demands at the base of these structures at the design basis, maximum considered, and failure level earthquakes. These results showed that the rotation and strain demand at failure level earthquakes were comparable regardless of the ground motion. Ultimately, this FEMA P695 approach verified the R factor of 6.5, C d factor of 5.5, and Ω 0 of 2.5 for C-PSW/CFs with boundary elements.