This project investigates the use of weak column-strong beam (WCSB) moment frames for seismic resistant design. A recent analytical study of such a steel frame indicates that WCSB frames may have greatly increased ductility demand and reduced available ductility over that obtained in comparable strong column-weak beam (SCWB) structures. This raises a question as to whether these recent changes are conservative. In this study rational guidelines for the design of frames with the WCSB configuration will be developed. The inelastic seismic behavior of steel building frames of different heights and geometry subjected to different seismic design criteria and acceleration records will be analyzed. The analyses will consider and compare the response for WCSB frames, comparable SCWB frames, and frames with weak columns at isolated stories or single column lines. The ductility demand will be computed and compared for the various conditions, and the comparison will isolate a few conditions for further experimental evaluation. The results will provide a better understanding of the behavior of weak column frames and form a basis for improved design procedures. This research proposal has received the support of the Structural Engineers Association of California (SEAOC) Seismology Committee in a resolution passed June 18, 1988, and formal approval of this support by the SEAOC State Board of Directors is pending. It is also supported by the American Iron and Steel Institute (AISI) Seismic Building Codes Committee, and this committee will establish an Advisory Panel for the conduct of the research. Several professional engineering associations and code committees including the Structural Engineers Association of California (SEAOC) endorsed this study due to the practical significance of the subject.
