Seismic Design Criteria for Steel Moment Resisting Frames for Collapse Risk Mitigation
This paper quantifies the lateral overstrength and the collapse risk of steel buildings with perimeter special moment frames (SMFs) designed in highly seismic regions in North America. State-of-the-art analytical models that consider the contributions of the composite concrete slab and the interior gravity framing to the lateral resistance and strength of steel frame buildings are employed. The findings demonstrate that the quantification of system overstrength based on dynamic analysis is more appropriate to nonlinear static analysis, since dynamic amplification of story shear forces due to higher mode effects is considered. Collapse risk is quantified using the mean annual frequency of collapse. It is found that low to mid-rise SMFs designed with a strong column weak-beam (SCWB) ratio larger than 1.0, achieve a probability of collapse larger than 1 percent in 50 years. A tolerable probability of collapse is achieved when a SCWB > 1.5 is implemented into the seismic design of steel SMFs.
Record created on 2016-09-11, modified on 2016-09-11