The Key Technology Research Of Low Prestressed Carbon Fiber Reinforced Concrete Girder Bridges

Currently, the carbon fiber reinforcement method, with its advantages, has beenfavored by many domestic scholars. Carbon fiber reinforcement method has manydrawbacks and can not give full play to the high tensile properties of carbon fibers,Therefore, many scholars have proposed prestressed CFRP, This reinforcement method inthe bridge area of research has been made part of the results. However, this method islimited by the tensioning equipment, it led to the impracticability of prestressed carbonfiber reinforced. The actual project with prestressed CFRP is seldom.This paper follows the practicality and simple operation,it prestressed low-prestressedCFRP method based on prestressed CFRP. The theoretical calculation method ofLow-prestressed reinforcement method is derived. And using12rectangular beams withanti-arch external steel strand method did static load test. It studied the reinforcement effectby loading history, prestressede level,verified the correctness of the results of the theoreticalanalysis. By static load test study drew conclusions about:1) CFRP sheets beams failed to improve ultimate strength, CFRP does not play a rolein pre-loaded, Exists stress hysteresis. It can suppress the development of cracks afte yieldload. The form of final destruction is debonding.2) The Low prestressed CFRP sheets initial strain reaches758×10-6works best.Prestressed CFRP sheets ultimate strength can be increased44%~61%, improve the yieldload, suppresses effectively the development of cracks.3) The stiffness of Low Prestressed CFRP beams is improved.Almost no pre-loadedcracks develop and it improved the cracking load, reducing the growth rate of deflection.4) The beams with Low Prestressed CFRP is close original one.the reinforcingmember ensure its deformability.5) When Low prestressed CFRP reinforcing member initial strain reached551×10-6,the component failure modes of CFRP is pulled off. There is no obvious signs ofdamage after yield load. It belongs to brittle fracture.6) This paper verifies the correctness of derivation of CFRP prestressing.