JOINT SIMULATION WITH SHEAR KEY AND WEDGE EFFECT FOR LIGHTWEIGHT PRECAST SLABS

Abstract

Roofs and mezzanines built with lightweight prefabricated elements have two major drawbacks: the longitudinal joints between elements and the permeability of said joints. If continuity is to be achieved in the slab, a joint is required to guarantee the transmission of stress to the adjacent elements, and its design to ensure the watertightness of the slab and the slab in general. The present study was focused on a joint with a shear key and wedge effect, which had already been used in the Residential Building System (SER) with good structural results, but not from the point of view of waterproofing. Based on this, it was decided to analyze the behavior of two types of joints, one completely filled with resistant mortar and the other applying an adhesive, waterproofing and elastic material in the lower part of the joint, filling the rest of the cavity with mortar. In the study, the Finite Element Analysis was carried out in several scenarios, with slabs of 3.61 m in length. With the results, it was possible to verify that the two types of joints have a favorable structural behavior before the application of the loads, perceiving that the slabs are deformed as a whole and with small displacements. This confirms that type 2 joint can be used for roofs and wet areas of mezzanines, guaranteeing both resistance and structural rigidity, as well as impermeability.