Abstract:
Near-end enhanced embedment (NEEE) prestressed carbon fibre reinforced polymer (CFRP) strip is an innovative, efficient and economical technique to reinforce the concrete structure. The CFRP-concrete interfacial bonding performance in NEEE section is the key factor to anchor prestressed CFRP and ensure high efficiency of reinforcement. To clarify the bonding performance of CFRP-concrete interface in the inclined embedded section, which is a part of the NEEE section, nine single-shear pull-out tests with respect to concrete prism specimens were carried out. Factors such as the angle of oblique grooves, embedded depth of CFRP strips and bond length of strengthened region were investigated. Additionally, a bond-slip model of the local interface was presented. The test results show that the load-bearing capacity and fracture energy of specimens increase with the increase of oblique groove angle. The interfacial bonding performance has a positive correlation with the embedded depth of CFRP strips and reaches a maximum with the embedment ratio of 50%, and do not change significantly thereafter. The proposed bond-slip model based on test results could accurately predict the debonding process of CFRP strips in the inclined embedded section.