This paper studies performing progressive collapse analysis for steel structures using the requirements of recent codes released by the United States Department of Defense and the General Services Administration. Based on review of the code requirements, nonlinear dynamic progressive collapse analysis results in a more uniform factor of safety than linear static analysis. The Applied Element Method in structural analysis is proposed as an efficient alternative for performing progressive collapse analysis. A case study is undertaken where the results of progressive collapse analysis using traditional finite-element-method simplifications are compared to the results from the Applied Element Method in the analysis of a moment-resisting steel frame. The case study shows that simplifications that are usually done in finite element analysis when studying traditional load cases can be over-conservative when performing progressive collapse analysis. The results show that the use of the nonlinear dynamic Applied Element Method while taking into account the effect of secondary members such as slabs and secondary beams can lead to considerable savings in the total weight of the steel frame.

A. Khalil, Enhanced Modeling of Steel Structures for Progressive Collapse Analysis Using Applied Element Method, Journal of Performance of Constructed Facilities, ASCE, Available online 3 August 2011, ISSN: 0887-3828 (print) 1943-5509 (online).