EFFECTS OF INFILL WALLS ON BUILDING BEHAVIOUR UNDER SEISMIC LOADS

In the design of Reinforced Concrete (RC) building, infill walls are normally assumed as non-structural elements and they are accepted as vertical uniform loads on beams. Therefore, the RC buildings are designed as bare frame structures. However, in reality, infill walls are present in RC buildings, and the seismic performance of the buildings will be different with and without infill walls.  In this study, 5 storey RC buildings with 2 bays and 5 bays in X-direction and Y-direction respectively are considered. The infill walls were replaced as equivalent diagonal struts and the non-linear static pushover analysis was performed to evaluate the effects of infill walls on the overall performance of the structures. The lateral strength capacity and performance point of the building were determined for the conventional (bare frame) method and with the presence of infill walls. The study reveals that the effects of infill walls under seismic loads in significant until elastic region in which the initial stiffness and strength of the structures increases, while lateral deformation capacity decreases. It is also observed that there are no significant changes in terms of ultimate lateral strength and roof displacement of the building as compared within presence of infill walls and bare frame.