Structural Static Analysis Of Self-Anchored Suspension Bridge With Lightweight Composite Deck

Along with the massive construction of municipal bridge, self-anchored suspension bridge has been more and more valued among the medium-small span bridge because of the advantages such as without anchorage structure and flexibility of structure. The dissertation explains the history and structure features of the self-anchored suspension bridge initially and then introduces the current development of bridge deck pavement. Based on these facts and connecting to the self-anchored suspension design of Chengdu Yizhou Avenue Jinjiang Bridge, the dissertation has done the research about self-anchored suspension bridge in three aspects from static analysis of the whole bridge, local stress analysis of steel box girder anchorage structure, and to light composite bridge deck structure.Firstly, the dissertation introduces the method to initial state of whole bridge. The method first does precise analyse of catenary cable element, which is, cable shape through nodal line method and then input initial internal force to get the final initial state of whole bridge. Next, finite element model is applied to verify the rationality analysis of initial state and static analysis. The result finds that the whole bridge meets all requirements of standards even under the under the most unfavourable load combination of deformation and stress. Meanwhile, the dissertation discuses the longitudinal force of steel box girder when use light composite bridge deck structure.Considering the importance complexity of anchorage structure behind the steel box girder, the dissertation analyses the general rule of main cable anchorage system design of self-anchored suspension bridge and finite element software is used to analyse the local stress distribution of post anchor structure. So as to shorten the bad influence of vertical force of cable, measures including tensile bearing and partial loading are taken. After that, main cable anchorage system can transport main cable force to steel box girder through anchor tensile plate in reasonable stress.Next, in order to solve the problem of significant spatial effect of wide deck under stress, the dissertation discusses distribution and computing method of the orthogonal anisotropic plate system and uses Midas-FEA space plate element model to analyse of stress distribution. In order to shorten the roof stress, the dissertation compares the situation about the steel box girder stress distribution and the deformation response when using asphalt pavement and STC pavement scheme. Meanwhile, Midas space plate element model keep used to simulate different loading position of fatigue-loaded vehicle and calculate the fatigue problem of steel box stiffening girder bridge. The research finds that lightweight composite bridge deck can efficiently to improve the deck stiffness, shorten steel plate working stress, and decreases fatigue stress-range of fatigue hot parts.Finally, the dissertation has done the parametric sensitivity analysis of supertoughness concrete pavement system. The parametric analysis mainly focuses on the STC elastic model, STC layer thickness, the vertical stress from fatigue-loaded vehicle to pavement system, horizontal stress, shearing strength of pavement layer under adverse loading position.which can be used to core parameter selection of STC deck design and optimization bridge structure design.