Analysis on mechanical behavior of river-crossing pipeline under flood action considering two-way fluid-solid coupling
In order to solve the problem that the one-way fluid-solid coupling of the river-crossing pipeline under the action of flood does not consider the influence of pipeline on the flood,resulting in inaccurate results.A two-way fluid-solid coupling fi-nite element calculation model of flood-pipeline was proposed.Based on this model,the mechanical behavior of pipeline stress,displacement and vibration frequency under different factors was analyzed.The results show that the pipeline stress and displacement are strongly positively correlated with the flood velocity and the suspended length,and the pipeline has the risk of yield failure and deformation failure,especially for the oil pipeline.The vortex-induced vibration frequency of the pipeline is strongly correlated with the flood velocity and the suspended length,and the increase of these two factors leads to the in-crease of the resonance risk of pipeline,especially for the gas pipeline.The alternating load caused by vortex-induced vibra-tion leads to the cumulative damage of pipeline,and the pipeline has the risk of fatigue failure.Therefore,the preventive measures should be taken to deal with flood disasters in pipeline design,with special attention to the influence of flood veloci-ty,suspended length and conveying medium,so as to avoid the pipeline damage.The research results have reference value for the safety evaluation and reliability research of river-crossing pipelines.