Flexural, Compressive Arch, and Catenary Mechanisms in Pseudostatic Progressive Collapse Analysis

Progressive collapse has drawn significant attention from researchers because of its potential to inflict severe damage and casualty. Much research has focused on simulation techniques for collapse, but comparatively little has examined the interactions among the three main mechanisms of flexural, compressive arching, and catenary actions by way of simplified methodologies. This paper introduces a theoretical method to calculate the collapse resistance of reinforced concrete frame structures in static progressive collapse analysis. The lumped-damaged plasticity method was used to simulate flexural analysis, and compressive arch and catenary actions were calculated using geometry analogies assuming rigid body rotation after initiation of plastic hinging. The method was validated by comparing the simulation results with experimental data, wherein reinforced concrete beam-column assemblies subjected to column removal were tested pseudostatically. The flexural and arching actions were well predicted by the proposed methodology, though the assumed failure mechanism at the end of the simulated catenary action was conservative compared to the experimental results. Overall, the developed method integrating flexural, compressive arch, and catenary actions during collapse was found to be a reliable tool for quick estimation of collapse resistance in static progressive collapse resistance.