Local Stress Analysis Of Fixed Pier-Tower-beam Part Of Long-span Cable-stayed Bridge Applied In Rail Transit

Thanks to the development of constructional technique and deepgoing research of the cable-stayed bridge, the cable-stayed bridge has showed up in the realm of Rail Transit in the1980s. In recent years, a number of cable-stayed bridges have also been built in China. This thesis firstly introduce the following content:evolution and the supportive system of the cable-stayed bridge for Rail Transit, and submodeling method based on St. Venant principle and relative knowledge for local stress analysis. Then a full-bridge finite element model was established by professional bridge computing software MIDAS, taking a cable-stayed bridge with main span of250m in Chongqing as the project background. The internal force and deformation of the bridge in all constructional and operational stages are calculated and analyzed, in order to gain the boundary conditions for the local model established subsequently. The methods for choosing boundary conditions and simulating prestressed tendon when using universal finite element software ANSYS are discussed. After comparing the advantages and disadvantages of three real-tendon methods usually used in simulating prestressed tendon by ANSYS, an optimized constraint equation method based on APDL was proposed. Then the local model of fixed pier-tower-beam part of the bridge was established by ANSYS. The stress and its distribution under adverse load combination was analyzed in detail, thus, the security and rationality of the design were checked. Finally, suggestions for improving the design were given.