动态加载模拟凹坑对管道模型压溃影响
Influence of Denting Under Dynamic Loading on Subsea Pipeline Buckling

海底管道在埋设以及使用过程中极易产生凹坑缺陷, 凹坑会影响管道的局部屈曲, 对含凹坑缺陷管道的局部屈曲研究十分必要．当前对凹坑形成过程通过简单的静态加载进行模拟, 这与实际工程实践中落物撞击的动态过程不符．本文采用有限元软件ABAQUS运用动态加载的方式对管道凹坑形成过程进行模拟, 在此基础上对含有不同凹坑深度、宽度的海底管道进行局部屈曲的数值模拟, 与压力舱管道试验结果对比, 验证模型的正确性．对比分析动态加载与静态加载模拟凹坑的管道结果, 结果表明：动态加载与静态加载两种方式对管道凹坑的模拟存在差异, 当压头撞击管道的动能达到一个临界值后, 动态加载模拟凹坑的管道模型的压溃压力小于静态加载的压溃压力, 用静态加载模拟凹坑的管道模型分析大质量压头高速撞击形成凹坑的管道存在安全隐患．
Denting easily occurs during the burial and use of subsea pipelines，and denting defects influence the local buckling of subsea pipelines. Therefore，it is important to study the local buckling of subsea pipeline with denting defect. At present，researchers use static analysis method to simulate the denting which may be different from the actual process. Finite element software ABAQUS was used to numerically simulate the local buckling of subsea pipelines with denting under dynamic loading，and the simulation result was verified through the comparison with the result for the pressure cabin experiment. The comparative analysis of denting under both dynamic loading and static loading shows that there is some difference between the two loading methods. Simulation of pipelines with denting using static loading is not accurate enough in practical construction，it may be not safe to simulate denting under static loading when the indenter impacts the pipelines with large mass or high speed