Study of the Dynamic Reaction Mechanism of the Cable-Stayed Tube Bridge under Earthquake Action

In order to explore the failure mode of the cable-stayed pipe bridge under earthquake action, taking the structural system of an oil and gas pipeline-cable-stayed pipe bridge as the research object, the full-scale finite element calculation model of the cable-stayed pipe bridge-oil and gas pipeline structural system as well as the finite element calculation model considering the additional mass of the oil and gas medium and the fluid-structure interaction effect were established by using ANSYS Workbench finite element software. The stress and displacement of the cable under the earthquake action were analyzed in the time history, as were the response characteristics of the cable when subjected to both methods. The calculation results show that the overall failure of the pipeline is basically the same under the two methods. Compared with the additional mass method, the solution for the fluid-structure coupling method can be derived through a comprehensive analysis of the flow field and structure, respectively, avoiding the sudden change caused by model simplification or calculation error so that the analysis results can better simulate the actual situation. In summary, the fluid-structure interaction method enables a more precise prediction of the dynamic response of the structure, and the findings of this research can provide a theoretical foundation and technical guidance for optimizing the seismic performance of cable-stayed pipe bridges.