中文摘要：

本文运用ABAQUS有限元软件模拟深海输油管道的后屈曲及屈曲传播现象.将深海输油管道视为内、外层为合金钢材,夹心为聚氨酯泡沫的输油管道.采用线弹性-线性硬化的本构关系,运用Riks分析法获得后屈曲平衡路径,以此模拟管道中的屈曲传播过程,并获得屈曲传播压力.通过数值算例,综合讨论了不同初始缺陷、不同径厚比、不同夹层与夹心厚度比对、不同的材料弹性模量对屈曲传播过程和压力的影响.最后将输油管退化为单层管,将传播压力的有限元结果与实验结果、Palmer理论解比较.结果表明有限元值、实验结果、理论值三者比较吻合.验证了有限元分析的正确性.

英文摘要：

This paper presents a finite-element approach to simulate the unique phenomenon of post-buckling and buckle propagation in undersea thermal insulation pipelines. The thermal insulation pipelines consist of a polyurethane foam core, sandwiched between an outer and an inner pipe made of steel. A bilinear elasto-plastic material model is used to describe the stress-strain relationship in the pipes after collapsing. Using Riks method the post-buckling equilibrium path is obtained and is used to simulate the buckle propagation procedure. Buckle propagation pressure is acquired from the post-buckling analysis. Parametric analyses are conducted to investigate the effect of initial imperfection, radius-thickness ratio, facesheet-core thickness ratio and the Young’s modulus of material on the buckling and buckle propagation performances. Finally, the finite element predictions for a single wall pipeline are obtained and are compared with the available theoretical solutions and experimental results. It is found that they are in good agreement, validating the finite element simulation.