Evaluation of the Bond Strength Models between Fiber Reinforced Polymers and Concrete

In recent years, the use of fiber-reinforced polymer sheets (FRP) for strengthening and rehabilitation of concrete structures has increased significantly due to their positive characteristics such as low weight, high tensile strength, resistance against corrosion and harsh environmental conditions, ease of application and electromagnetic neutrality. One of the most important parameters in the study of behavior and modeling of reinforced concrete structures reinforced with externally bonds FRP sheets is the bond strength between FRP sheet and concrete member. So far, various relationships have been proposed to estimate the bond strength of FRP sheets loaded by external forces. Some of these relationships depend on variables such as concrete compressive strength, cross-section width, FRP sheet width, concrete and FRP elastic modulus, and etc. Some other proposed relationships for the ultimate bond strength, in addition to the previously mentioned parameters, the maximum local bond strength is also considered as effective parameter. It should be noted that based on previous research, the maximum local bond strength is itself function of a factor called the width factor, which is an important parameter in defining the specifications of the external continuous reinforcing layer at the concrete surface. One of the most challenging challenges for engineers in more accurate modeling of reinforced concrete structures reinforced with FRP sheets is the existence of an accurate relationship for estimating this bond strength the prevent local slippage of the reinforcing sheet. Therefore, the main purpose of this study is to evaluate accuracy of the models presented for bond strength of FRP sheet and concrete surface using a database consisting results of 253 experimental tests presented in previously published studies.

کلیدواژه ها:

Concrete structures ، Bond strength ، Tensile strength ، FRP