Experimental and Analytical Assessment on RC Interior Beam-Column Subassemblages for Progressive Collapse

Abstract

Experimental and analytical studies carried out on a RC moment-resisting frame after it is subjected to the loss of its ground-story exterior column is presented in this paper. Four full-scale interior beam-column subassemblages with varying degrees of nonseismic detailing were subjected to a monotonic loading regime to simulate the effects of redistributed gravity loads on the subassemblage after the loss of an exterior ground column. The variables in the test specimens include the beam longitudinal reinforcement ratios and the spacing of the transverse reinforcement within the beams, columns, and joints. The load-displacement relationships, crack development patterns, and failure mechanism obtained from the tests are also discussed. The finite-element models are validated by comparing the results with the experimentally obtained data. Parametric studies are then performed to study the influence factors, such as the beam transverse reinforcement ratio and the incorporation of an additional exterior beam-column element and slab on the global behavior of the subassemblages. © 2012 American Society of Civil Engineers.