Experimental evaluation of new details for connections of post-tensioned flat slabs to steel columns

One type of structural systems that has received growing attention in recent years, includes post-tensioned flat slabs and steel columns. This system has significant economic and professional advantages. But, seismic behavior of the connection between flat slab and steel column, which is principally designed for gravity loads, is in doubt. In this regard, these connections should have sufficient ductility under lateral deformations. Although details for the connections of nonprestressed slabs to steel columns are published in the technical references, which usually include steel shear heads, but specific details for post-tensioned slabs have rarely been published in the literature. In this study, new details have been proposed for the connections of post-tensioned flat slabs to steel columns. These details include horizontal steel plates, vertical steel stiffeners and high strength shear bolts. To evaluate the proposed details, a half scale test specimen was built and was subjected to lateral cyclic loading with increasing amplitude. The test shows that the proposed connection could withstand relatively large displacements up to a drift of 6%, without loss of strength and/or gravity bearing capacity and/or significant failure. According to this study, the proposed details have sufficient ductility under lateral loading and provide a favorable seismic performance.