ANTI-COLLAPSE ANALYSIS OF UNEQUAL SPAN STEEL BEAM–COLUMN SUBSTRUCTURE CONSIDERING THE COMPOSITE EFFECT OF FLOOR SLABS

摘要

Based on the alternate load path method and considering the composite effect of floor slabs, a beam-column frame with unequal spans was studied to derive the equations for the load-deformation relationship at five different stages (elastic, elastic-plastic, plastic, transient, and catenary) during progressive collapse. The anti-collapse mechanism of the composite beam-column frame and the influence of arch action were carefully analyzed. A numerical model was established using ABAQUS for the relevant model, and the model was verified by comparison with experimental data. Further, the theoretical equations were compared with the results of numerical simulations for different span ratios. The results show that the theoretical equations possess good generality and high accuracy for analyzing progressive collapse of a composite beam-column frame with unequal spans. Copyright (C) 2019 by The Hong Kong Institute of Steel Construction. All rights reserved.