Experimental Reach On Shear Of Bonding Interface About Steel Fiber Self-stressing Concrete Reinforcement Of Existing Structure

Reinforcement of the existing concrete structure, the quality of rein force impactson the structure of the normal use of functionality and security directly. Alsodetermine the economic benefits of the huge amount of reinforcement costs.Vulnerable part of old and new concrete combination is still the joint surface.The main factors about impact of new and old concrete interface mechanicalproperties are the main interface roughness, surface roughening method, using theinterface agent, reinforcement materials and mixture ratio, temperature variation, theimpermeability and the interface structure treatment mode. This article take theLiaoning Province department of education scientific research project (L2010378)as the research background. The steel fiber reinforced concrete for strengtheningexisting structure interface shear properties of a large number of experimentalresearch. On the basis of previous studies, the experimental study conducted in-depth.On the size and structure of complexes is described in detail, the test load and the datacollection process in strict accordance with the " standard methods for testing ofconcrete structures ", also carried out the simulation software of ANSYS and analyzedon the basis of test, and the simulation result and test data are compared. The maincontents are as follows:1、The six groups of new and old concrete combination and one group of oldconcrete specimen shear experiment. Comparison of the containing structurereinforcement of steel fiber reinforced self stressing concrete, containing no structuralreinforcement of steel fiber reinforced self stressing concrete, Containing structurereinforcement of ordinary concrete, not containing the structural reinforcement inconcrete, interface using artificial chiseling under four conditions of new and oldconcrete and the shear behavior. Experiments show that: steel fiber reinforcedconcrete in structure reinforcement effect, improves the connection of new and oldconcrete and the shear performance.2、The interface structure reinforcement in different reinforcement ratio underconditions of shear experiment. We had got the different reinforced conditions on the combination of shear behaviors. The experiments show that: with the combination ofsurface adhesive rate, Interface stress level is enhanced, and compared to the ordinaryreinforced concrete shear stress maximum value increased obviously, sheardisplacement and crack width are reduced.3、Through the seven groups of specimen shear experiment results analysis,concrete shear strength enhancement factors are:(1) Steel fiber reinforced selfstressing concrete as a new concrete reduces direction shrinkage deformationeffectively along the interface.(2)The constructed of reinforced expansive in theinterface play an effective constraint, so that the new old concrete interface togenerate a compressive stress. A study about7groups of specimens of the shear stress-shear strain and shear stress-crack width curve, Summed up the characteristics ofthe test after no crack-cracking-destruction stage and so on.4、The comparative analysis of the experimental result and numerical simulationresult shows that the steel fiber self-stressing concrete combined structurereinforcement can improve the interface’s capacity of shear deformation effectively,Elimination the distribution situation of the new and old concrete interface shearstress basically.5、Through to the shear stress and shear strain, shear stress and crack width curveand the trend of research, summed up the test after not crack stage-crack stage-destruction of the phase characteristics. Put forward " The method of interfacestrength reduced " method to realize the finite element modeling about new oldconcrete interface, and the test results and simulation results are in good agreement.