Analysis On Box Girder Structure And Stress Of Long-Span PC Continuous Rigid Frame Bridge

Bridge as a across structure,which play a pivotal role on the development of the economic and social. Prestressed concrete continuous rigid frame bridge is a good overall structure, spanning capacity, reasonable force, a simple and neat form of concrete bridge, while maintaining a continuous beam without joints, smooth driving characteristics, but also T-Gang no bearing frame bridge, construction of convenient features, so the bridge construction in the world, especially the domestic bridge construction, and prestressed concrete continuous rigid frame bridge has been rapid development, as across the Gulf, valleys, rivers One of the main bridge structure. On the other hand, with the prestressed concrete continuous box girder bridge construction and use, about the kind of bridge-type of disease more and more. One outstanding question is:Web impact structure appeared normal use or durability of the principal tensile stress cracks; main beam deflection under the late deformation and large common than the design value. The emergence of crack deflection and excessive production of structural safety, durability, and normal use have had a very negative impact.In this paper, rigid frame Ziyang Han River bridge support projects, the access to large amounts of data, based on carrying out the following three areas:1. To the related basis of the information, summarized the impact of continuous rigid frame bridges cracking some of the important factors.2,Using the bridge analysis software Midas / Civil different from the web thickness variations and the different slope of the continuous rigid frame box girder bridge under web principal stress and vertical deflection analysis of the impact study, and on this web structure based on a number of optimization is discussed, and changes in the structure of the web structure of the force and vertical deflection in a number of favorable laws.3,Use common software ANSYS to establish pier across the web and near the top of web space near the finite element model of the vertical distribution of stress in the web field distribution in the analyzed, meanwhile, two vertical prestress distribution of tectonic stress field are compared, As the basis for a viable given vertical force structure to reduce the vertical prestressing tendon damage, and enhance web reserve vertical pre-stress, reduce the probability of cracks and web size.4,Through the establishment of general software ANSYS 1 / 4 full bridge space finite element model of a real bridge the various vertical prestressed continuous rigid frame bridge on the web principal stress analysis of the impact study, and on this basis given the kinds of prestressed force on the webs of rules and control measures for longitudinal prestress loss, to make pre-web reserves increased stress, stress is more reasonable to reduce the probability of cracks and the web size, and enhance the structure security, durability and normal performance.