SEISMIC RESPONSE OF GRAVITY COLUMNS IN BUILDING WITH SHEAR WALLS

Abstract

In flat slab building, the concrete slab rests directly on the columns. This system is highly in demand these days especially in metro cities due to ease in construction, low floor to floor height requirement and space use flexibility. This system is well, capable to resist all gravity 'loads safely but it becomes vulnerable to damages under seismic loading. Due to such incapability of this system to resist lateral loading safely, many building codes restrict its use, without any lateral load resisting element, to zones of lower .seismic vulnerability areas only. In this dissertation work shear wall and perimeter beams has been provided to resist all the lateral loads. Different flat slabs building with shear wall and without shear wall has been analysed using ETABS-2000 software package. When shear wall has not been provided then huge amount of reinforcement is required in gravity columns, but after providing perimeter beams in the structure the bending moments and shear forces in the gravity columns has reduced significantly. In another study both perimeters beams as well as shear wall have provided in the building to study the behaviours of gravity columns. From the results it was observed that the bending moment and shear forces in the gravity columns have reduced further. Therefore flat slab building with lateral load resisting system can be provided in higher seismic zone areas. To study further orientation of shear wall has changed to know the effect of shear wall on gravity columns. The model in which shear wall has provided at the core of building and beams are provided at the perimeter exhibit the best behaviour for resisting the lateral-loads. The beams, columns and shear wall designed as per IS-456 and IS-1392 to estimate the amount of reinforcement. Total five models have analysed in this present study and for every models amount of concrete and steel required are calculated. It was found that minimum structural cost is required for model M5, in model M5 shear wall has provided at the core of building and beams has provided at perimeter.