Collapse Evaluation of Steel Structures

The R factors first proposed were based largely on judgment and qualitative comparisons with the known response capabilities of relatively few seismic force resisting systems in widespread use at the time. Since then, the number of structural systems addressed in seismic codes has dramatically increased. As a result, the seismic response characteristics of many systems, and their ability to meet seismic design performance objectives, are both untested and unknown.In an attempt to address these issues, the Applied Technology Council (ATC) was commissioned by Federal Emergency Management Agency (FEMA) under the ATC-63 Project to develop a methodology for quantitatively determining global seismic performance factors for use in seismic design.Though this Methodology is originally recommended for use with model building codes and resource documents to set minimum acceptable design criteria for standard code approved seismic force resisting systems, in this report it is used as a basis for evaluation of a steel moment frame designed in 1970's to achieve intended seismic performance objectives.This work should help students and professionals interested in seismic analysis of structures.