Effects of Floor System on Progressive Collapse Behavior of RC Frame Sub-Assemblages

Abstract

The ability to predict the resistance of reinforced concrete (RC) structures to progressive collapse as a result of an interior column removal has become a need in structural design. In general, three resistance mechanisms characterize the structure resistance to progressive collapse, flexural action, compressive arch action, and tension catenary action. The objective of this study is to investigate the effects of floor system configurations on the progressive collapse-resistance of RC frame sub-assemblages and the amount of energy dissipated in each resistance mechanism. This investigation employs a fiber element-based modeling technique to present findings into the effects of beam size and reinforcement details on the progressive collapse-resistance and energy dissipation of RC beam-column sub-assemblages with four equal spans. Three different span lengths of 5, 6, and 7 m were considered. A total of 38 floor system designs for gravity loads were performed in accordance with the ACI 318-14 design code. The modeling technique employed in this study was validated and utilized by the authors in previously published works. The study shows that beam size and the presence of slab are critical as they significantly affect the energy dissipation and progressive collapse-resistance and failure pattern of the sub-assemblage frames. Moreover, the presence of a slab was found to increase the energy dissipation by around 28%.