A New Measure to Reduce the Potential for Progressive Collapse of Steel Frame Structure

Abstract

In order to improve the capacity of resistance to progressive collapse for steel frame structures, a new measure, which uses bracing systems to help damaged frame to bridge across the local damage caused by abnormal loads, is presented in this study. The dynamic progressive collapse analysis is carried out to investigate the effect of resistance to progressive collapse in two different cases of column removal. Analytical results show that bracing systems on the top of steel frame structure have obvious effects on collapse prevention. Comparison with the unbraced steel frame structure, fixing bracing system could decrease the vertical displacement of the node corresponding to the top of the removed columns, and reduce the moment peak value at the end section of beams. And after column removal, plastic hinges come into being in the unbraced steel frame, on the other hand, there are no plastic hinges formed in the steel frame with bracing system.