Experrimental Research And Engineering Application Of Variable Binding Reinforcement Technology By Prestressed Carbon Fiber Plate

As a kind of reinforcement material with high tensile strength, good corrosion resistance, long durability and other characteristics, the carbon fiber plate gets more and more widely attention. Based on a set of carbon fiber plate t ensioning machine and anchorage,this article puts forward a new method of reinforcement—the variable binding of RC beams strengthened by prestressed CFRP. Using this technique can effectively overcome the disadvantages of the traditional method of non pre stressed reinforcement,such as the intensity of carbon fiber sheet is inadequate, the improve of stiffness is limited, The use of organic adhesive stickers have poor durability,it can also give full play to the carbon fiber plate reinforcement and prestre ssed reinforcement technology, the variable binding strengthening technology with prestressed carbon fiber board not only has the advantages that construction is simple and fast, but also has the advantages that can significantly improve the emergence and development of crack, improve the durability of strengthened structure. According to the effect of variable binding strengthening technology to reinforced structure this paper does the following aspects of the work.Firstly, in the laboratory, experiments were made to study the anchorage performance of layering type anchorage.Above two 3 m long H steel beams, we tensioned the four manufacturers of 10 kinds of different width and t hickness of the carbon fiber plate.By the test results,The anchorage performance of layering type anchor is good and it can completely meet the need of practical engineering.Secondly,By using a set of self-developed prestressed carbon fiber plate(CFRP Plate) anchor and stretching machine, CFRP were stretched and anchored on the surface of three concret beams with long 5.6m, experiments were made to study the change of bonded prestressed CFRP reinforcing concrete flexural member, The ductility of the concrete flexural member and the emergence and development of cracks were comparative analyzed of the use inorganic binder, organic adhesive and using electric heating device in the previous bond and no influence on later bond between the CFRP and concrete flexural member.,The test results show that, the variable binding of RC beams strengthened by prestressed CFRP can significantly improve the form of cracks, it has a good strengthening effect.Lastly, application of the reinforcing system, the research group conducted the actual reinforcement project of Zhujindu bridge in Hunan Province. Puted forward the scientific and effective method, and developed a simple and high efficiency construction technology. Based on the reinforcement test showed that, the use of variable binding prestressed reinforcement system has good reinforcement effect.At the same time, used in a fiber bragg grating sensors on the surface of the CFRP, made long-term strain monitoring carbon plate after reinforcement, studied the effect of environmental temperature, carbon plate anchorage slip and creep on the reinforcement effect. The research results show that the prestressed carbon plate reinforcement system had good performance for a long time, using variable binding prestressed carbon fiber board has great application value in the bridge reinforcement.