Bond slip behavior of anchored CFRP strips on concrete surfaces

• The strengthening of RC walls by using CFRP strips was an effective technique.
• The strip configurations were effective on the hysteretic behavior of wall.
• CFRP strips are not effective initial lateral stiffness of the specimens.
• Displacement capacities of specimens have been improved by strengthening technique.
• Strengthened specimens are dissipated much more energy than reference specimen.

In this study, strain distributions and the bond slip behaviors at the carbon fiber reinforced polymer (CFRP) strips and reinforced concrete interface were investigated. 14 concrete specimens with externally bonded CFRP strips were tested. Main variables considered in the experimental study were width of the CFRP strips, bond length of CFRP strips and the number of anchorages. The test results obtained from the experimental study are comparatively presented in terms of strain distributions on CFRP strips with anchorages, stress – displacement behaviors, initial stiffnesses, energy dissipation capacities of test specimens. From the test results it is observed that using anchorages is very effective in terms of ultimate load capacity, strain distribution and energy dissipation capacity. The results of the experimental study are compared with analytical results obtained from several bond strength models available in the literature. A bond slip model was proposed based on the results of the conducted tests. It was observed that bond stress of the CFRP strips increased with increasing number of anchorages.