Seismic Behaviour of Slab-column Connections with Various Punching Shear Enhancement Methods

A series of slab-column connection specimens have been tested under reversed horizontal cyclic loading and constant gravity loads during the last years at NOVA School of Science and Technology. These specimens have been tested under similar loading conditions, using a test setup that simulates slab continuity in the longitudinal direction, the same overall dimensions (4.15m × 1.85m × 0.15m) and approximately the same flexural reinforcement ratio of 1%. Various punching shear enhancement methods have been tested, including stirrups, headed studs, fibre-reinforced concrete, high-strength concrete and post-installed bolts. This paper presents a summary of the reported tests and a comparison of the main results, with the purpose of comparing various punching shear enhancement methods for seismic loading conditions. The results from different experimental campaigns are compared. It is shown that relatively large drift ratios at failure are achieved by employing punching shear reinforcement in the form of stirrups or headed studs. However, less conventional methods such as fibre reinforced concrete and high strength concrete are shown to be promising alternatives. Compared to the reference specimens (without any punching shear reinforcement or other enhancement) that failed at 1% horizontal drift, the other specimens failed for significantly higher drifts, ranging from 2.5% to above 6.0%.