An evaluation of the GSA Nonlinear Static Progressive Collapse Methodology applied to EC 8 Seismically Designed RC Moment Frames

Abstract

This study aims at evaluating the progressive collapse potential of RC framed structures designed to Eurocode 8 with varying design ground accelerations and ductility classes. Four typical 11-storey RC framed structures were designed with ground accelerations of 0.10g and 0.25g at low, moderate and high ductility classes. Analysis of the performance levels and progressive collapse vulnerability of these structures was carried out considering the four column loss scenarios and acceptance criteria specified by the General Service Administration (GSA) document. It was observed that high design ground acceleration and low design ductility classes increase the progressive collapse resistance of EC 8 designed RC framed structures. This observation is counter-intuitive to the principles underpinning the EC 8 design code as higher design ductility class is expected to enhance the energy absorption capacity or ductility of buildings with same design seismic action but varying ductility classes. It is concluded that the use of GSA to assess buildings designed to EC 8 must be modified to include the effects of both design action and design ductility class of a structure. The location of the lost column was also found to be very influential on the progressive collapse resistance of the structure.