Experimental evaluation of composite floors under column loss scenarios

To better understand the performance of steel-concrete floor slabs under a critical column removal, two large-scale composite floor systems were tested at The University of Texas at Austin under two different column removal scenarios. Early analytical research indicates that floor slabs play an essential role in mitigating collapse. Nonetheless, the limited experimental data currently available provide inconsistent results. The main objective of the experimental program was to identify basic behaviors of composite floor systems and to estimate their ultimate capacity under the absence of a critical column. The specimens were representative of isolated regions of the gravity-load resisting system of a typical steel-framed building, with simple shear connections and no provisions to mitigate disproportionate collapse. Both specimens were tested under quasi-static loading conditions. Detailed finite element models were developed and validated against the collected experimental data. Using the validated numerical models, the collapse load under sudden column loss was estimated.