Date of this Version



Composite, steel, concrete, earthquake engineering, structures, structural sngineering, speedcore, somposite plate shear walls – concrete filled, FEMA P695, seismic design, R factor


This report summarizes the results from FEMA P695 analytical studies conducted to verify the seismic design factors for composite plate shear walls – concrete filled (C-PSW/CF), also referred to as Speedcore. ASCE 7-16 provides the seismic design factors, which include the seismic response modification factor, R, deflection amplification factor, Cd, and overstrength factor, Ωo, for various approved seismic systems. C-PSW/CFs are assigned a response modification factor of 6.5, a deflection amplification factor of 5.5, and an overstrength factor of 2.5 for C-PSW/CFs. These seismic design factors were selected based on the seismic performance of similar structural systems and engineering judgment of the committee. This analytical study investigated and verified the appropriateness of these seismic design factors for walls with flange plates as boundary elements.

Four planar (3-story, 6-story, 9-story, and 12-story) and three C-shaped (15-story, 18-story, and 22-story) C-PSW/CF walls were analyzed following the FEMA P695 procedure. This procedure included development of representative planar and C-shaped C-PSW/CF archetypes, calibration of numerical models for these archetypes, and evaluation of nonlinear static (pushover) and incremental dynamic (time history) analyses. The results indicate that seismic design coefficients of R = 6.5, Cd = 5.5, and Ωo = 2.5 appropriately quantify the seismic performance of C-PSW/CF with boundary elements. Walls without any boundary elements or closure plates are not recommended for seismic design based on supplementary analytical studies.