EFFECT OF CHLORIDE CONTENT ON THE BOND BEHAVIOR BETWEEN FRP AND CONCRETE

Many structures strengthened by FRP composites may locate at seaside and the chloride content may be a threat to the durability of the strengthened members. Many investigations have been conducted to study the durability of concrete or FRP composites itself under different sever environmental conditions, but less attention has been put on the durability problems of the concrete members strengthened by FRP composites. In the present study, both experimental and theoretical investigations have been carried out to study the effect of chloride content on the debonding behavior between concrete and FRP plates. To study the debonding behavior between FRP and concrete, direct shear test is often performed. Before the test, the specimens were submerged in the salt solutions with the concentration of 10% for different periods (0 days, 15 days and 30 days). And then, the specimens were dried and tested to obtain the initial and ultimate debonding loads, together with strain distributions along the FRP plates at different load values. A three-parameter model was employed to analyze the debonding behavior between concrete and FRP plates. With the tensile strains along the FRP plate at different load values, the effect of chloride content and submerging period on the debonding behavior will also be studied.