Seismic performance of damaged crumb rubber concrete frames retrofitted with carbon fibre-reinforced polymer

In this study, the seismic performance of damaged crumb rubber concrete (CRC) frames retrofitted with carbon fibre-reinforced polymer (CFRP) wrapping was investigated. A beam-weakening technique was employed to enhance ductility and achieve a more desirable failure mechanism by shifting damage from brittle column and joint failure to a ductile beam failure mode. Two 1/3 scale models were tested: one representing normal concrete (NC) and the other CRC. The retrofitting technique restored ductility up to 82% for NC frames and 76% for CRC frames, with response modification factors of 90% and 81%, respectively. The study demonstrates that CFRP retrofitting effectively redistributes damage, resulting in a more uniform cracking pattern and improved energy dissipation capacity. These findings underscore the potential of CRC as a viable option for seismic applications, offering enhanced sustainability without compromising structural integrity.