Openings in slabs are usually required for plumbing, fire protection pipes, and ventilation ducts and air conditioning.
This study presents an experimental investigation on the influence of openings on the punching shear strength of high reinforced concrete flat plates. Five models of slab-column connection of (1000 x 1000 x 70mm) simply supported along the four edges are tested. The slabs are loaded concentrically by a central stub column. The main variables studied are the size(100x100mm and 200x100mm)and location(at 35 mm , at 135mm from center of slab and at the corner of slab) of the openings and used steam curing method.
Experimental results are recorded and studied at various stages of loading, deflection at the center of the slab, at distance (150mm) from the center of the slab in two directions and at the edge of the tested slab out of support. First cracking load and ultimate load capacity are also recorded.