FEM Analysis And Experimental Study On Shear Strengthening For RC Beams By Steel Plates With Direct Shear Bolts

There are a lot of the mature reinforcement method domestic and overseas, which have made a lot of good results, but these techniques have their own shortcomings. Our group to develop reinforcement system with the direct shear bolt steel plate has many advantages relatively. The core of this technology is adopted direct shear bolt as fitting of reinforcing steel and concrete, ensure that anchor group have same stress. Steel plate will have stress from the beginning together with concrete, the stress of the anchor bolt group is also very uniform. This can greatly improve the stiffness and bearing capacity of components, it also can effectively control the occurrence of cracks and development, improve the ability of component damage of ductility. The technology can effectively avoid stripping damage of steel plate and make full use of the anchor bolt and steel plate material strength. Fire performance is better than steel sticking method.As we can see there are so much experimental study on bend capacity of beams reinforced by anchor bolt steel plate domestic and overseas, in some cases, some empirical formulas are put forward, but study on shear capacity of beams is less. In the practical engineering, we often meet with situation that need for the shear reinforcement. In this article, through combination of finite element analysis and experiment validation, further study on direct shear bolt plate shear reinforcement mechanism and its influencing factors. This has important significance to guide the engineering practice and promote technology.The content of this thesis consists of:(1)FEM analysis: In the first discussed the anchor bolt element in the finite element software ABAQUS, considering preliminary test results, to determine the reasonable bolt element model. Then use the anchor bolt element to establish finite element model of beam with the direct shear anchor plate shear reinforcement. Based on the parameter analysis, discuss the influence of shear reinforcement effects in different reinforcement concrete beams, such as the number of anchor bolt, size of steel plate and stirrup reinforcement ratio;(2)Experimental research: Conduct the shear reinforcement test with three full sized rectangular beams using direct shear bolt steel reinforcement technology. Contrast experiment is carried out on end of each beam, and the strengthening experiment is carried out on the other end. By measuring the deflection, bearing capacity, steel strain and shear angle of two test components, discussed the technology of reinforcement effect and its influencing factors;(3)Conclusion: By a comprehensive discussion of test results and the corresponding finite element analysis results to get the conclusion, direct shear bolt plate can improve concrete beam shear bearing capacity and stiffness, effective control of the development of the cracks, and steel anchor reliably and can avoid stripping damage. Direct shear bolt plate shear reinforcement effect by the stirrup ratio, number of anchor bolt, steel plate size and other factors. Also can consider to use the technology when section does not meet the constraints.