SEISMIC RESPONSE OF A RC FLAT-PLATE COLUMN-SHEAR WALL SYSTEM

Abstract

Flat-plate structures are considered to be inadequate for regions of high seismicity and are considered as gravity-resisting system. Hence, it is important to evaluate these structures and improve the seismic resistance of systems that are found to be vulnerable. The seismic response of the structure was predicted using nonlinear static analysis known as Pushover Analysis . Pushover Analysis is a relatively simple way to evaluate the design of a structure compared to Nonlinear Dynamic Analysis. A certain predefined structural loading pattern is applied to the structure which causes weak links and develops failure modes. FEMA 356 criteria were used to evaluate the seismic performance of the case study buildings: five storey and ten storey. The three performance levels (Immediate Occupancy, Life Safety, and Collapse Prevention) were checked using global-level evaluation that is interstory drift limit. Based on the seismic evaluation, shear walls were added to the structure, with different percentages of floor area (1%, 2% and 3%). The results of the study clearly show that the flat-plate buildings cannot survive in Maximum Considered Earthquake of Zone IV and fails in punching shear. Primary lateral load resisting system such as shear walls should be combined with flat:plate s wh ich_are_gravity_resisting_system ._ Add ition-o f-sh ear—walls -inc reases-the-strength and stiffness of the structure. Shear walls should be placed symmetrically to the structure with long walls.