Bond behavior of near surface mounted CFRP rods under temperature cycling

A near surface mounted (NSM) strengthening technique using CFRP rods has been developed to increase the load-carrying capacity of deteriorating concrete structures compared to that possible with traditional external bonding techniques. This paper investigates the bonding behavior between the CFRP rod and the concrete under temperature cycling when the near surface mounted (NSM) strengthening technique is applied. A total of 27 pullout specimens were fabricated and tested to investigate the effects upon filling materials of applying various numbers of temperature cycles from −15 to 55 °C. The test results included failure load, average bond stress, strains in CFRP bar, and failure mode.