If unpredictable loads are applied to flat slab-column connections, punching shear failure occurs with almost no warning signs. To prevent progressive collapse of flat slab-column connections, it is necessary to provide a secondary load carrying mechanism after punching shear failure. In this research, some suggestions for establishing, an alternative mechanism in flat slab connections after punching failure are proposed. For this purpose, an experimental program was conducted to investigate the post-punching behavior of 17 slabs with various reinforcement layouts and concrete covers. The effects of integrity, compressive, shear, truss, and bent-up reinforcements, diameter of tensile reinforcement, and concrete cover of tensile reinforcement on the postpunching behavior of slab-column connections were studied. The results of the experiments indicate that the integrity reinforcement significantly improves the post-punching strength. The increase of the concrete cover of the tensile reinforcement and decrease of the diameter of the tensile reinforcement result in an increase of the post-punching strength. Bent-up integrity reinforcement increases the punching and post-punching strengths, simultaneously. Truss reinforcement significantly improves the punching and post-punching behavior.

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