The Local Simulation Analysis Of Large Span Prestressedconcrete Cable Stayed Bridge

The beam sections of modern cable-stayed bridges are of large width and various forms. Some times the precise stress distribution cannot be obtained with plane analysis. The partial stress caused by large concentrated force is very complicated, in the cable-girder anchorage zones and prestressing tendon anchorage zones. So, the analysis model established suitable or not, the structure internal-force, deformation and the stress though the model established suitable or not, the structure force, the deformation and the stress distribution in the result are directly affect.In this thesis, a cross line cable-stayed bridge in Zhengzhou is taken as a case study. Based on the result of integral finite element model analyzing by MIDAS, a detailed finite element mode for the beam segment is established by ANSYS, and the stress distributions of the beam segment under some loads case is calculated. Especially for the top plate, the web and the base plate.The three-dimensional stress distribution of the beam under different loads are analysized. And the effect of boundary condition and concentrated force is discussed by comparing of the stress in different positions. The stresses by the three-dimensional prestressing tendon is also analyzed.The analysis models for other critical zones of the bridge are also presented, and the stresses of which's calculated. It is shown. The local tensile stress can be reduced effectively by using bending prestressing tendon or modifying the section form. Sometimes the structure form of the bridge partly depends on the simulation analyzing result of 0# block.It can be concluded from the analysis results, the model scale of local simulation analysis not only depends on the form of the beam, but also affected by the target needed. Comparing with the integral simulation analysis method or the beam element analysis, the local simulation analysis can obtained the complex stresses distribution. It can be the supplement of the beam element integral analysis, and improved the local structure.