PERFORMANCE STUDY OF RETROFITTED GRAVITY LOAD DESIGNED WALL FRAME STRUCTURES
Buildings designed primarily for gravity loads are prone to shear failures in walls, columns and beams when subjected to far field effects of earthquakes. Previously, pushover analyses carried out on these buildings were terminated when a local shear capacity was reached. However, in a recent study by considering shear yielding, ductile shear hinges were used to model the ultimate seismic behaviour of such buildings. This study suggested that for some cases, high-rise buildings in Singapore may incur some shear damage at the performance point. Also, experimental studies on typical components such as shear walls, wide columns and T-beam-wide-column-joints have suggested that FRP retrofit can be used to improve the seismic behaviour of such components. Based on these studies, macro-models are proposed to simulate the FRP retrofitted shear walls, wide columns and T-beam-wide-column joints. Using these models, the performance of the FRP retrofitted structures was studied against the seismic demand due to long distant earthquakes affecting Singapore using a previously proposed damage index for this type of buildings.