Punching shear reinforcing using studs with steel plates in reinforced concrete flat plates

Abstract

Flat plate structures of reinforced concrete buildings have many advantages. However, a drawback of flat structures is that they are vulnerable to punching shear failure at the column-slab connections. This study proposes a new novel technique to improve the punching shear resistance capacity in new flat plate structures using the studs with perforated steel plate reinforcement at column-slab connections. Tests were carried out on specimens of 3 4 scale, which were designed to fail as a result of punching shear. The specimen variables were as follows: the first case used a stud rail and a base specimen; the second case used four stud specimens with perforated steel plates with different lengths; and the third case used a perforated steel plate with the same length as the stud with the steel plate. From the test results, the following conclusions were drawn: (a) the ultimate strengths of specimens have been designed to resist punching shear based on ACI 421 and Eurocode 2-04, and shear reinforcement for slabs has been compared with the results from the structural experiments; (b) the studs contributed substantially to the increase of ultimate strength; (c) the studs with steel plates contributed to the increase of the ultimate strength. The ratio of ductility in the specimen was larger than that of the total increase in strength.