EXPERIMENTAL STUDY OF SHEAR PERFORMANCE OF CFRP REINFORCED CONCRETE INTERFACE

The bonding behavior between CFRP and concrete is one of the main factors affecting the mechanical properties of CFRP reinforced concrete structures. In order to study the factors affecting the bonding performance of CFRP-concrete, the double shear tests of CFRP-concrete interface bond properties were carried out according to different CFRP weight per square metre, CFRP layer number and concrete strength grade. Under different CFRP weight per square metre, different CFRP layer number and different concrete strength grade, the failure characteristics of the bond interface between CFRP and concrete were analyzed. Combined with its load-displacement curve, the failure mechanism of CFRP-concrete bonding interface was analyzed. The bond-slip curve was obtained by strain stacking, the slip amount and the maximum shear stress under different factors were analyzed, and the influence law of the slip amount and the maximum shear stress under a single factor were obtained. The test results showed that the failure of the specimens occurred between the concrete surface layer; and the strength grade of the carbon fiber cloth could increase the ultimate bearing capacity and the maximum shear stress of the interface, but different CFRP weight per square metre had little effect on the ultimate bearing capacity and the maximum shear stress of the interface; the relative slip of CFRP decreased with the increase of CFRP mass per unit area, CFRP layers and the strength grade of concrete.