Roughness Effects on the Fracture Energy between FRP and Concrete

The single test is carried out on totally 54 concrete samples with 6 different interface-roughness conditions, as to delve into the influence of concrete surface roughness on the concrete-FRP interface. Accordingly the closed-form solution based on the compressive strength and interface roughness parameters of concrete is acquired. As the research result indicates, the extremum and extreme point exist in terms of influence of concrete surface roughness on fracture energy, the model acquired in line with the test data is appropriately applicable under the condition 0.34 <= f(i)<= 0.56, and such model is overall applicable under the concrete strength of 30MPa <= f(c0)<==50MPa. The model proposed hereof in this paper is superior to the existing models, as not only the significant contribution made by concrete strength to fracture energy is considered, but the influence of concrete surface roughness on interface is highlighted.