The External Prestressing And Carbon Fiber Reinforced Joint Concrete Continuous Beam Research

The exterior prestressed concrete structure has many advantages as a branch of the prestressing system. Due to the relative simplicity of the construction process of the exterior prestressed structure, the convenient concreting and the effective increase of the concrete’s quality and durability, the external prestressed structure is widely used in the actual bridge project to reinforce bridge. Many scholars, both home and abroad, have launched a large number of experimental studies. At the same time, Carbon fiber composite materials, widely used in the field of reinforced repair, possess the property of lightweight, high strength, corrosion resistance, ultraviolet and so on. However, there are few studies about using carbon fiber to reinforce the exterior prestressed concrete structure home and abroad. Especially when the Bond-slip characteristics of the interface between the carbon fiber and the concrete are considered, there is no precise explanation of mechanical deformation performance of the reinforced exterior prestressed concrete structure continuous beams. For this case of continuous beam’s wide use in the actual bridge engineering, the designer’s first-hand experimental data and the design theory are needed, like the stress and the strained condition of the reinforced exterior prestressed concrete structured continuous beams under the vertical load stress and other mechanical properties as well as economic benefits. This paper, based on the basis of the exterior prestressed concrete structure, studies the strained mechanical properties of the reinforced concrete continuous beams by high-performance polymer carbon fiber composites, so that the structural materials can play its role to the fullest, the current theoretical defects can be solved, and the further analysis of the reinforcing technology of the beams bridge can be made.In order to study the deformation of the exterior prestressed concrete continuous beams reinforced by carbon fiber after a force acting on, a test study, nonlinear finite element numerical analysis, theoretical studies of analytic solution of the deformation properties are used in this article, to illustrate the mechanical property’s improvement of the exterior prestressed beams and the reinforced normal beams, compared with the exterior prestressed concrete continuous beams reinforced by carbon fiber. The main content of this paper is as follows:(1) An overview of the exterior prestressed concrete structure is put forward, briefly explaining the advantages and disadvantages of the carbon fiber reinforcing the concrete structure, describing its development and research at home and abroad, and raising relevant issues for further analysis;(2) In order to study the mechanical strained condition of the exterior prestressed concrete continuous beams reinforced by carbon fiber, three sets of two-span continuous beam specimens are produced. Compared with static load test under the same load influence, the data of the tested beams’load, deformation and cracks on different mechanical stages are gained;(3) ANSYS10.0finite element numerical analysis software is applied to make the simulated analysis of the testing beams, based on test data measured. Bond-slip characteristics of the concrete and the carbon fiber materials are taken into consideration during the analysis, and the non-linear deformation research is also carried out. The study result shows that, the load-displacement curve, the stress--state of the beams and the relationship of displacement’s distribution along the beams length agree well, thus proving the consistency and reliability of the numerical analysis;(4) Based on the experimental data and numerical results, the theoretical study of the deformation properties of the ordinary exterior prestressed continuous beams and the exterior prestressed concrete continuous beams reinforced by carbon fiber is put forward. This paper uses differential equations to derive the analytic expression of the force-method and equationforce-method equationequation of the force method of the exterior prestressed beams under vertical load, and the distribution curve of the deflection along the beams direction is obtained. Due to the Bond-slip characteristics of the interface between the concrete and the carbon fiber materials, the deformation of the reinforced beams are analyzed under the contact theory. The theoretical deriving result is broadly consistent with the experimental result and the numerical results, so the theory presented in this paper is feasible to analyze the deformation properties of the beams.Through the research on the normal use of the exterior prestressed concrete continuous beams reinforced by carbon fiber, the displacement of various parts and the distribution of the stress along the beams are derived, and the accurate analytical formula of flexivity and stress are given in this paper. A simple, clear and practical computational theory is provided to the designers.