EVALUATING THE SEISMIC RESPONSE OF FLAT PLATE MULTISTORIED STRUCTURAL SYSTEMS WITH THE INFLUENCE OF WEAK STOREYS

Abstract

Now a day’s multistoried buildings are common in urban regions due to increase in human population and civilization towards urban regions, FSI(floor space index)permission is decreasing day by day in urban region due to that buildings are getting increase towards vertical. To fulfill the high head room requirements, flat plate or flat slab or beam less floor systems have come into existence and in
multistoried building parking storey is common in ground floor which will lead to weak storey or sift storey formation and this soft storey is not much capable enough to transfer the inertia forces generated due to earthquake. Therefore in this particular study we consider G+12 storied building symmetrical about longitudinal and transverse direction, 7 different mathematical FEM 3D models have been generated in ETABS2015, an attempt is made in this study to nullify the soft storey effect by incorporating lateral resisting elements in the form of shear wall and steel bracings. To evaluate the seismic response two types of seismic analysis have been done via linear equivalent static and linear dynamic (response spectrum analysis) have been performed as per IS-1893-2002 and 2016. FEM modeling have been done by considering columns as frame element having 6DOF at each node, slab, shear wall and masonry infill
panel haven been modeled as thin shell elements having 4 nodes and each node has 6 DOF and Lateral bracings are modeled as frame elements having 6DOF at each node with moment released at each nodal point. Finally a suitable building configuration is suggested for the practical implementation