Experimental Research On Flexural Performance Of Reinforced Concrete Beams Strengthened With Prestressed CFRP

Carbon Fiber Composite reinforced concrete members has been widely used in the field of Civil Engineering as a new reinforcement technology. A lot of experiments about it were performed by many research institutions in China and abroad, and a lot of valuable theories were gotten. But in the practical engineering the using of CFRP reinforced concrete members still exists certain defects:The concrete components strengthened with CFRP has been in a certain state of stress before it was strengthened, but after they were served load again, the stress of CFRP is far less than that of concrete, which leads to the high strength performance of CFRP can not be brought into fully. In order to reveal prestressed CFRP reinforcement effect on the performance of reinforced concrete beams, the two groups of eight different reinforcement ratio of concrete beams strengthened with CFRP and prestressed CFRP were studied for their bending performance in this paper. A set of prestressed CFRP tension device to solve the technology of CFRP tensioning was designed in the paper. The yield load, ultimate load, steel strain, crack development, bending stiffness and other performance indicators of the concrete beams which strengthened with prestressed CFRP were analyzed in the experiment, and reinforced effect was compared among the prestressed CFRP,the ordinary CFRP, different prestressed CFRP. Comparing the theoretical calculation and ANSYS finite element simulation with the experimental results.The results show that, the high performance of CFRP can be gotten fully by using prestressed CFRP reinforced concrete beam, and concrete beams which strengthened with prestressed CFRP are more significantly improved in bearing capacity, stiffness and other performance indexes than those of concrete beams which strengthened with ordinary CFRP, and the bigger the prestressing force is served, the more obviously the effect was improved, and put forward the simple calculation formula of yield load and ultimate load were optimized.