FEMA P695 Study – “Enhanced Ductility” RC Coupled Wall Systems

Research purpose

The proposed study will examine the application of the FEMA P695 Methodology to ED-RCCW buildings less than 240 ft. in height to determine appropriate values of R, Cd, and Ω0; for buildings greater than 240 ft. tall, ASCE 7 requires a dual system. The study will follow the same general approach as used for the trial studies outlined in NIST (2010) for RC shear wall buildings as summarized by Gogus and Wallace (2015). A single configuration, with two cantilever walls coupled by a single “column” of coupling beams over the building height will be considered to illustrate findings for a range of building heights and design parameters. Important design variables are anticipated to be coupling beam aspect ratio (ln/h) and strength (Vn), and wall cross section geometry, i.e., planar wall versus flanged wall cross section. The expectation is that trial values of R, Cd, and Ω0 will be selected, and the objective of either confirming these values or iterating to refine these values. Iteration may be limited to a subset of the initial study.

University of California - Los Angeles (UCLA)
Project Area
Structural Engineering
CPF research grant #
Award amount
Grant period
Jul 2017 - Oct 2018
Grant Status
In Progress
Principal Investigator
Professor John W. Wallace - UCLA; Co PI - Kristijan Kolozvari, California State University Fullerton
Industry champions

James Harris, S.K. Ghosh, Laura Lowes, Ron Klemencic, David Fields

CPF allies
Research deliverables
  • 90% Draft ASCE 7 building design examples
  • 90% Draft of nonlinear analysis results
  • Final Report