INFLUENCES OF PRIMARY DESIGN PARAMETERS ON PROGRESSIVE COLLAPSE RESISTANCE OF REGULAR RC FRAME STRUCTURES

Progressive collapse is defined as the localized damage propagating throughout a structural system, which is triggered by the initial failure of critical structural element(s) caused by abnormal loads, eventually resulting in a partial or total collapse of the entire structural system. The progressive collapse resistance of the structural system is significantly affected by its redundant strength. The influences of primary design parameters on the progressive collapse resistance of regular reinforced concrete (RC) frame structures were analyzed and summarized to satisfy the requirement of rapid engineering assessment. Eighteen typical RC frames with regular configurations were designed according to the codes in which the effects of three design parameters, i.e., seismic fortification intensity, total number of structural floors and structural span, on structural redundant strength were considered. The numerical models of the frames were established using fiber beam elements, in which beams were modeled with T-shaped sections considering the contribution of the floor slab within the effective flange width. The nonlinear dynamic alternate path method was utilized to analyze the progressive collapse responses of these frames when initial failure occurred at different locations, and the influences of the primary design parameters on the progressive collapse resistance of the structures were studied. © 2023 Tsinghua University. All rights reserved.