波流联合作用下海底管道侧向运动数值分析

研究旨在提出波流联合作用下海底管道侧向运动数值模拟分析方法。通过建立三维离散刚体模拟海床，梁单元模拟海底管道，设置了两个载荷步模拟管道与土壤接触的过程，解决了实体模型不易收敛的问题。分析了不同管—土法向行为接触刚度、不同管—土切向行为摩擦系数、不同波流参数以及不同单位长度管道水下质量对海底管道侧向运动的影响。研究表明：海底管道的最大等效应力、最大侧向位移、最大接触压力以及最大横向摩擦剪应力对于管—土法向行为接触刚度的变化并不敏感；管道的最大侧向位移随着管—土切向行为摩擦系数增大而减小，呈现出线性变化的关系；当波高一定时，管道的最大侧向位移随着流速的增加而增大，并且波高越小，最大侧向位移随流速增加的速度明显越大；管道最大侧向位移随着单位长度管道水下质量的增加而减小，并且呈现出线性变化的关系。

Numerical simulation of lateral movement of submarine pipelines under wave-current interaction

This study aims to propose a numerical simulation method for analyzing the lateral movement of submarine pipelines under wave-current interaction. By establishing a three-dimensional discrete rigid body to simulate the seabed, beam elements to simulate the submarine pipeline, and setting two load steps to simulate the process of pipe-soil contact, the problem of convergence difficulty in solid models is resolved. The influence of different pipe-soil normal behavior contact stiffness, different pipe-soil tangential behavior friction coefficients, different wave-current parameters, and different underwater unit length pipe masses on the lateral movement of submarine pipelines is analyzed. The results show that the maximum equivalent stress, maximum lateral displacement, maximum contact pressure, and maximum lateral friction shear stress of submarine pipeline are not sensitive to the variation of pipe-soil normal behavior contact stiffness. The maximum lateral displacement of the pipeline decreases with the increase of pipe-soil tangential behavior friction coefficient, showing a linear relationship. When the wave height is constant, the maximum lateral displacement of the pipeline increases with the increase of flow velocity, and the smaller the wave height, the faster the increase of maximum lateral displacement with flow velocity. The maximum lateral displacement of the pipeline decreases with the increase of underwater unit length pipe mass, showing a linear relationship.