Test Research And Theoretical Analysis Of Deformation Performance Of The RC Beam Strengthened With CFRP

Throughout history, so far from the end of World War II ,about 60 years, the construction industry has gone through three different periods of development , which is new building in large-scale,new building and reinforcing the old building. Statistics show that China is in development from the first into the second period of development .During the process, on the one hand new construction is being built; On the other hand, the construction which can not meet the needs of the community as a result of many factors, This is largely to promote the building of the technical aspects of reinforcing research. FRP has been widely used in concrete structure reinforcing , because of its high tensile strength, convenient construction, durable resistant, suitable for many ways, light weight, do not to increase the section size etc.However CFRP reinforcement used in concrete technology is far ahead of practical application in the design of the development of the theory. Most scholars and limited to bending, shear, pressure test, as well as the basic fatigue, durability, bond strength studies .After the CFRP reinforced concrete structure , the way of structure's deflection to carry out, crack width, deflection and how to calculate, there is no mature research results about these problems at home and abroad. In the" the technical point of order about carbon fiber sheet reinforced concrete structure" (CECS146: 2003), paragraph 4.3.5, it is also clear that: "because of no mature research results, there isn't been given the reinforcement about cracks and deformation's check approach ", It needs further study.In this paper, the method of combining metheoretical analysis and experimental research was used to study the anti-cracking performance and deformation of pre-splitting CFRP reinforced concrete beams. The test used the 10-Test-beam with the same cross-section, including 2 comparison beams and 8 CFRP reinforcement beams. The main considerations are concrete strength, the ratio (reinforcement ratio and the bar's diameter), as well as the thickness of the protection ,in total three factors, using two static load. The studies include the following:1)to explore the development of the cracks and deflection of CFRP reinforced concrete beam above stage of the normal use.2) search for the CFRP reinforced concrete beam's cracks and deflection's impact factor in the stage of the normal use.3) giving the calculation mode of cracks and deflection about the reinforced concrete beams4)ANSYS finite element analysis program analyzed the reliability of the calculation model.The study shows that CFRP reinforcement can inhibit the development of the deflection and cracking. Basing on the model of reinforced concrete beam crack and calculation, the text got the calculating maximum crack width model of CFRP reinforced concrete beams., it gave the stiffness and deflection's calculation modle of reinforced concrete beam. The results of ANSYS analysis, theoretical calculations and experimental results agree well with measured values, achieving the objectives and research purposes. It provided a scientific basis to improve the CFRP reinforcement technical specifications, the method of reinforcement and the development of reinforcement technical.