Bonding Experiment Research Of Crankshaft Specimen FRP-concrete Interface

With the rapid development of national traffic transportation, structure reinforcementtechnique is more and more important, fiber reinforced concrete structures has been becomingthe research hot spot, and interfacial bonding mechanism research of FRP-concrete is animportant content of fiber reinforcement technology. So far, research results are mostly basedon test regression, and lack of theoretical foundation, meanwhile there is bigger differencebetween computed results and test results, thus real debonding process can’t complete reflect.Moreover, to crankshaft specimens, because of complexity of their interface mechanicalbehavior, present strengthening methods are severely lack of theoretical support, analysis ofinterfacial stress still follows planar paste, coupling of interfacial normal stress and shearstress and impact of curve surface string debonding effect are not taken into consideration tothe interfacial stress. Thus, bonding mechanism research of crankshaft specimenFRP-concrete interface has significant engineering application value.First, the paper designed26crankshaft specimens with different curvature to researchinterfacial bonding mechanism research of FRP-concrete. By studying concrete strength, FRPboding layer and length of carbon fiber and specimen curvature, the paper researched theiraffect on ultimate bearing capacity; provided the change curve of bonding shear stress anddebonding normal stress along forced direction of carbon fiber under different leves loads ofreinforced specimen; analyzed change law of middle span deflection; explored Interfacedebonding failure mechanism and stress transfer process.Secondly, on the basis of existing studies, by analysis and summary of test results,introducing curved surface stickup influence factor, the paper gained the optimized interfacialbonding strength formula of crankshaft specimen FRP-concrete and bond-slip constitutivemodel. Through the comparison with experimental results, the model is identical with testresults and effectively reflect Interfacial debonding bearing capacity and Interfacialdebonding process of crankshaft specimen.Finally, the paper analyzed and summered the test results, and prospected the researchresult of the paper to reinforce crankshaft specimen, and put forward further researchproposal.