The goal of this collaborative research is to provide much needed experimental data and effective modeling approaches for the disproportionate collapse analysis of older reinforced concrete flat-plate buildings that are commonly used for large residential and office complexes. Experimental and analytical studies will be conducted to examine the performance of such flat-plate structures under the scenario of a sudden loss of a column during an extreme loading event. The experiments will be performed on laterally restrained slab-column connections under static and dynamic loading and multi-panel specimens subjected to sudden load release. The tests will be conducted to provide data to define key parameters needed for analytical modeling, to identify the local strength and deformation capacity of the flat-plate systems, and to study the post-punching behavior of slab-column connections. Finite element simulations will be employed to facilitate the design of experiments, to determine local deformation demands, to define failure propagation characteristics, and to examine the effects of other design parameters not considered in the experiments. Simplified analytical tools will also be developed for quick evaluation of the progressive collapse resilience of flat-plate buildings without conducting a detailed finite element analysis.
The research in this project will lead to improved design guidelines for safer flat-plate buildings under extreme loading events. The data obtained from this study will also help in the development of appropriate rehabilitation approaches for flat-plate structures that are vulnerable to disproportionate collapse. Research findings will be disseminated to the structural engineering community through publications, presentations, and websites created for this project. High school students and undergraduate students will be engaged in this project to enhance their research interests in engineering. Research results will be integrated into the graduate level courses related to slab structures, and the project will provide advanced training to graduate student through their involvement in the project research activities.