Experimental Investigation on Punching Behaviour of Slab-Column Connections with Vertical Steel Sheets

This paper provides test results of punching shear-reinforced slab-column connections formed by prefabricated vertical steel sheets, developed to optimize the construction process. To evaluate the punching performance of this novel punching shear key, one slab without shear reinforcement and six slab-column connections with vertical steel sheets have been tested to analyze the influence of the thickness, number, and layout of steel sheets on punching shear behaviour. The tests revealed that vertical steel sheets significantly enhanced punching shear capacity. The principal strain directions in the region of vertical steel sheets that act as resistance to punching shear were concentrated between 40° and 60°. Brittle punching failure occurs with or without the installation of vertical steel sheets in slabs with high flexural reinforcement ratios. Additionally, the punching shear strengths predicted by ACI318, MC 2013, and GB50010 were compared with the test strengths. Overall, the vertical steel sheet system is a highly effective and simple option for improving the punching shear behaviour of slab-column connections.