Mechanical performance of concrete strengthened by modified epoxy resin bonded CFRP

Mechanical performance of concrete strengthened by modified epoxy resin bonded CFRP (carbon fiber reinforced polymer) is present in this paper, with particular focus on the interface bond strength and flexural strength. A type of modified epoxy resin adhesive which bonds CFRP sheets to strengthen plain concrete was developed. The interface bond strength between CFRP and concrete and the flexural strength of CFRP reinforced concrete were comprehensively tested. The influence of the CFRP size, number of CFRP bonding layers, and concrete strength was further analyzed. The results showed that CFRP significantly improved the maximum bearing capacity, displacement and failure energy of plain concrete. The bearing capacity of plain concrete improved almost linearly with an increasing number of CFRP layers. CFRP-reinforced low-density concrete has a better strengthening effect than high-density concrete. The final strength and failure energy of the CFRP-reinforced concrete increased significantly, compared to that of plain concrete. A model for calculating the maximum flexural strength of reinforced concrete structures is proposed.