Experimental Dynamic Response of Reinforced Concrete Flat Plate Sub-Structure under Collapse Scenario

摘要

The overall goal of this research is to evaluate the potential of disproportionate collapse in older reinforced concrete flat-plate buildings subjected to the loss of a supporting column. If a supporting column experiences failure, then the load must be redistributed to the surrounding connections. If the punching shear resistance of the surrounding connections is not sufficient, then a progressive collapse may result. The research program considers dynamic testing of isolated slab column connections that represent the connection near the lost supporting column. The dynamic tests are compared to static tests of similar specimens to determine the possible strength increase in the connection due to the loading rate. The test results show that the dynamic loading can increase the ductility of the slab by 23%, but did not show any increase in the connection strength. In addition, one multi-panel specimen representing a 0.4 scale 9 column section of a flat slab building was dynamically tested. The specimen was loaded with dead weight equivalent to the design load 1.0D +0.5L and an exterior column dynamically removed. No progressive collapse occurred in the flat plate structure.