A Review on Progressive Collapse Designing Based on UFC Regulation

Abstract
Progressive collapse is a relatively rare event which happens due to unusual loading on a structure that lacks adequate continuity, ductility and indeterminacy which causes local collapse in that structure and then extends it to other structural parts. In 2003, US defense department to published regulations UFC 4-023- 03 on the building design against progressive collapse and in 2009 submitted a revised version of the regulations. This regulation, based on the ASCE 7-05 standard, introduces two general approaches to building design against progressive collapse, including direct design and indirect design approaches. In this study, a variety of structural design methods for progressive collapse have been investigated. Moreover, their strengths and weaknesses have been mentioned. In general, the results of this study show that design based on AP is more economical than other methods. Also, using this method is much more commonly accepted by researchers and designers.