Application And Research Of The External Prestressed Technique In Continuous Beam Bridge Reinforcement

As time goes by and economy develops, more and more bridges cannot meet the demand of traffic. One of the most important methods to resolve this problem is bridge reinforcement and repairing, therefore, it becomes a hot issue in engineering. By studying on some regular reinforcement methods of road beam bridge, for instance, bridge deck pavement thickening, rib-beam augment, steel plate adhering, fiber material adhering, external prestressing method, structural system changing and etc., this paper, separately, introduces the reinforcement theories and characteristics of every method.This paper researches on external prestressing in a deep-going way. On the basis of studying domestic and abroad materials, design specification and related literatures, the paper systematacially researches on the structure of bridges strengthened with external prestressing, and carries through mechanical analysis of external prestressing system, combining curently degining matter and process of external prestressing reinforcement method in practice. The details of the paper include the following aspects:(1) Addresses status in quo of brigges home and abroad, the necessary and urgency of bridges reinforcement.(2) Finely analyzes the theory of bridge reinforement with strength of materials frndamental, discusses the reinforcement methods of road beam bridge and introduce every designing method of the reinforcement techniques.(3) By comparing common reinforcement methods of external prestressing, introduces the structure of external prestressing bridges and analyzes the external prestressing system.(4) Combining concrete engineering, finishes the design calculation of the external prestressing bridge, offering a reference for similar engineering.(5) As to concrete structure of external prestressing , for it affects security and trustiness of structure, the antisepsis of external prestressing cable is extremely important. This paper puts forward some measures to improve durability of external prestressing stucture.