Various Procedures for Progressive Collapse Analysis of Steel Framed Buildings

Abstract

Progressive collapse in a building occurs when major structural load carrying members (like columns) suddenly collapse due to accidental loads. Issue of progressive collapse of the building came into attention after the collapse of Ronan Point Apartment, London in 1968. After the collapse of World Trade Center (WTC) towers, many government and private authorities worked on developing design guidelines for progressive collapse-resistant structures. In this paper, four methods for progressive collapse analysis, namely, linear static, linear dynamic, nonlinear static and nonlinear dynamic analysis, are compared by analyzing a nine-storey steel moment-resistant frame building. The progressive collapse analysis is based on General Services Administration (GSA) guidelines published by the US government. Step-by-step descriptions of various procedures for progressive collapse analysis are given using commercially available structural analysis software, SAP2000. Since the issue of progressive collapse is not discussed in Indian standards, the main objective of this paper is to create awareness regarding the progressive collapse of building in a simple manner among practicing engineers.

Keywords: Progressive failure, Steel building, GSA guidelines, Linear static and dynamic analysis, Nonlinear static and dynamic analysis, Demand Capacity Ratio (DCR)