Study On Large Scale Damaged RC Beams Strengthened With Prestressed CFRP Plates

Reinforced concrete structures in service are affected by environmental factors (corrosion, temperature variations, precipitation, etc.), natural disasters (earthquakes, erosion, landslides, etc.) and human factors (vehicle overloading, terrorist attacks, etc.). They are prone to a variety of diseases, such as steel corrosion, cracks of concrete. The diseases will influence service performance and service life of structures. Moreover, the diseases will lead to collapse of the structures. Research on the reinforcement of RC structures is of great significance.CFRP plate is an ideal material for structural reinforcement for its high strength, light weight, corrosion resistance and other excellent properties. As an effective reinforcement method, prestressed CFRP plates reinforcement can effectively improve the bearing capacity, the stiffness and crack resistance of reinforced concrete structures. In this dissertation, the prestressed CFRP plates strengthing method on large scale damaged reinforced concrete beams was studied.The content of this work mainly contains:Firstly, performance tests of the wedge-type anchors and CFRP plates were conducted to get advanced understanding of mechanism of prestressed CFRP strengthening system. By these tests, the anchoring coefficient of anchors and mechanical parameters of CFRP plates were determined.Secondly, the stress procedure and calculation method of ultimate bearing capacity are analyzed. Simulate the RC beams strengthed with prestressed CFRP plates with ANSYS. Calculate bearing capacity and flexural stiffness, the influence of crack propagation, and the influential factors of the reinforcement.Finally, design the experiment of three groups of concrete beam, respectively, standard beams, less reinforcement beams and crack beams. By experimental studies, bearing capacity, deflection, crack and failure mode of the beams were studied. At the same time, compare the results of the experiments with FEM analysis and design results.