Seismic retrofit of RC frame buildings using FRP composite materials

Seismic retrofitting of reinforced concrete (RC) members using fiber reinforced polymer (FRP) composite materials has been an increasingly popular area of research in the last two decades. Progress on behavioral modeling of FRP retrofitted RC members, combined with recently developed performance based analysis and design tools allow for an analytical investigation of the feasibility of using FRP composites for seismic retrofitting of reinforced concrete frame structures. In this research, 2-D RC frames having square or rectangular columns are retrofitted in various configurations through FRP strengthening of beams for improved flexural capacity and/or wrapping of columns for additional confinement and resulting ductility. Nonlinear pushover analyses of frames before and after retrofitting are performed using a structural analysis software package that used custom-fed nonlinear parameters determined from separate analyses. Research results show a tradeoff between lateral load capacity and ductility of FRP retrofitted frames, revealing that either can be improved depending on the performance objective.