Construction Technology Of Reinforced Concrete Beam Strengthened With Prestressed Carbon Fiber Sheet

With the development of transportation industry in our country and the growth of the operating time, the transportation load and traffic volume are increasing, the bridge structure has been damaged in different degree, in the aspect of concrete beam bridge, the main damage performance is that bridge bearing capacity is insufficient, deflection of the beam is larger and some cracks under the beam is appearing, for the continuous rigid frame bridge, the cracks and excessive deflection are existing, wh ich affects the bridge aesthetics and traffic safety. In the process of the construction of old bridges in our country, most of the bridges belong to concrete beam bridge. In order to ensure the safety of driving, the research on the reinforcement of concr ete beam bridge is very necessary.In the process of pursuing simple and effective reinforcement method, the fiber reinforced plastic(referred to as FRP) has some advantages, such as lightweight, high strength and good durability, which makes the fiber re inforced plastic materials have good application and development in the field of civil engineering.At present, FRP has been widely used in the construction of concrete structures, but most of them are simply used in the surface of the structures, which cannot take full advantage of the high strength, considering the need of the construction of reinforcement, the strength of FRP is not fully used, the research of applying prestressing force on the materials is a new direction, the prestressed fiber reinforced material can not only give full play to the corrosion resistance, but also have a higher utilization of the material, and it can improve the anti-deformation capacity and bearing capacity, which has a better reinforcement effect.On the basis of referring to a large number of documents, this paper mainly studies the technical research and engineering practice of reinforced concrete beams with prestressed CFRP sheet. And on the basis of summarizing the theoretical research and engineering practice, the ex it problems and key control points are analyzed. In the continuous practice of engineering, Central Research Institute of Building and Construction Co. Ltd and Nanjing Hitech Composites Co. Ltd has research the prestressed carbon fiber sheet strengthening system, according to which, this paper introduce the construction technology detailed.Firstly, the paper introduces the application method of fiber composite material in the field of reinforcement and the prest ressed carbon fiber sheet strengthening system detailed, secondly, through the static test and fatigue test of the system, we prove its reliability, and according to the construction process, the quality control points of the reinforcement of the concrete beam are described, finally, the prestressed carbon fiber sheet reinforcement system is applied to the actual engineering, and it is introduced in detail in the paper, in the meanwhile, the strain of the fiber material is monitored during the construction process, and the prestress loss value of the system is finally obtained.The reliability and applicability of the system are proved by the laboratory system test and engineering practice in this paper, besides, through the analysis and summary of the reinforcement construction method and the construction quality control process of the pre-stressed carbon fiber sheet reinforcement system, the most accurate construction and acceptance data of the system are obtained. It do the basic work to promote the technology,and it also provides reference for the similar engineering practice.