| Carbon fiber is often used in the concrete structure reinforcement, anti-shock and prevention of corrosion and etc. Carbon fiber reinforcement has already applied in bridge reinforcement at present because its construction method has characteristics of economy, high efficiency and convenience. But the bonding agent specially used to bond carbon fiber currently is still lack. The price of bonding agent produced in foreign countries is high and has great differences in quality. Although JGN carbon fiber bonding agent produced in construction science institute in LiaoNing province is used more, it still has a great many defects. The following phenomena often happen. The violently polymerization is easy to happen when the temperature is too high. The brittleness failure is easy to happen and the safety is low when the flexibility of bonding agent condensate is not good. The simulation of the curer is great and not favorable to construction, health and environmental protection. Aiming at the problems mentioned above, the modified study is carried out on the system of epoxy resin bonding agent used currently. The experiment proves that epoxy resin and polysulphide rubber combine each other in the self-made bonding agent. Addition reaction of ethanethiol groups (-SH) and epoxy group happen, that is HS—[C2H2CH-2OCH2O(CH2)2-S-S]n(CH2)2-OCH2O(CH2)2-SH. The elongation at break of the bonding agent is greatly improved through the combination of long flexible chain of polysulphide rubber with the molecular chain itself of epoxy resin. The condensate in the structure of epoxy resin after consolidation has good flexibility. And at the same time, the optimum content of polysulphide rubber is 40phr. The shear strength decreased obviously if the content exceeds the optimum content.The experiment of self-made bonding agent shows that the flexibility of condensate increases but the shear strength decreases accordingly when the polysulphide rubber is added to enhance flexibility. And then the flexibility enchantment is not obviously if calcium sulfates whisker as the additive is used separately, but the effect is distinct if calcium sulfates whisker and coupling agent are used simultaneously. This can make up for the loss brought by the reduction of the shear strength. The optimum content of calcium sulfates whisker is 20phr. Therefore, the difficult problem that the shear strength is not reduced and the flexibility can be enhanced at the same time when polysulphide rubber and calcium sulfates whisker are used simultaneously will be solved. And this can meet the experience requirement.The paper relies on the project"the theoretical and experiment study on the technology of reinforced concrete bridge repair and reinforcement by carbon fiber composite material". This project is completed in the Transportation College of Jilin University. The paper mainly studies modified mechanism, method and process of carbon fiber bonding agent. In addition, the solidification mechanism, binding interaction mechanism in interface and filling enhancement mechanism are also introduced in the paper. The paper consists of five chapters totally. Of these chapters, chapters two, three and four are the more important part.Chapter one is the introduction. It mainly introduces the development state at home and abroad and the advantage and disadvantage of epoxy resin bonding agent. Correspondingly, the experiment project is put forward aiming at the disadvantage. Chapter two is the compose theory of the epoxy resin. It illustrates the basic performance and purpose of epoxy resin bonding agent. This chapter provides basis for the selection of compose materials in the further experiment.Chapter three is one of the most important parts. It mainly refers to the study methods and process of epoxy resin bonding agent modified experience. The modified mechanism mainly consist the following aspects. First, polysulphide rubber modified epoxy resin. Second, calcium sulfate whisker modified adhesive. Third, consolidation agent consolidates mechanism. Fourth, interfacial action mechanism. Fifth, enhancement fills mechanism. The GB/T 7124-1986 tension shear strength test methods, tensile performance experiment method of GB/T2568—1995 resin and testing machine are adopted in bonding modified experiment. Chapter four is also the significant part. This chapter introduces the study theory and methods of interfacial bonding strength in reinforced concrete beam strengthen with carbon fiber. The basic experiment of bonding strength is made. During the tensile course, the electro-hydraulic servo machine MTS is selected to exert classification load. The strain of each point should be recorded with the static data collection system of DH3816 when the classification load is exerted. According to the result, the flexibility enhancement and mechanical performance of carbon fiber bonding agent made-self is obtained.Chapter five is the last part. And this chapter is the summarization of this paper in which the content and direction are also pointed out for further study.
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