The Influence Of Concrete Strength On The Shear Resistance Of Concrete T Beams Reinforced By U-shape Carbon Fibre Bond Around Bars

Due to various reasons, more and more concrete structures need strengthening and new reinforcement techniques and reinforcement materials come into being.Among these materials, the fiber reinforced plastic (fiber reinforced polymer/plastic, FRP) is widely applied to reinforcing concrete structures because of its light weight, high strength, corrosion resistance, easy construction, etc. There will be debonding failure if traditional paste technique is adopted, especially in the process of shear strengthening.This paper adopts a new CFRP shear reinforcement method, which effectively prevents fiber materials from invalidating due to stripping in the process of strengthening.The author simulates the shear strengthening of continuous beams in the negative moment area through12T beams inversion test. The main work and research results are as follows:1. Through test, it is proved that the shear strengthening method through anchor by wrapping CFRP around bars carbon fiber band can effectively prevent T beams strengthening from invalidating due to stripping of fiber bands in the process of reinforcement, raise the shear-carrying capacity of reinforced beams remarkably and improve the stress and deformation of beams.2. Through tests, the effects on the damage forms and shear capacity caused by such factors as width and spacing of the fiber bands, the strength of concrete, etc. are studied.3. Based on the experimental records, the damage mechanism and stress model of reinforced beams are discussed, and the effective method to determine the fiber strain and the calculation formula of the shear carrying capacity are put forward and the calculation results fit closely with the testing data.