基于CEL的船舶抛锚撞击对海底管道影响分析

Influence of ship anchoring impact on seabed pipeline

沿海区域各类船舶抛锚作业对于海底管道的碰撞损伤风险不断提高。采用耦合欧拉-拉格朗日方法 (CEL)模拟了抛锚撞击海底管道过程。采用Mohr-Coulomb模型模拟海床的非线性特征,并利用罚函数法处理锚、海床与管道之间的相互作用。通过对不同土壤特性、落锚速度、锚自身尺寸及重力和管道埋设深度的参数分析研究了其对管道撞击塑性变形的影响,分析结果表明,埋设管道上部土壤特性在吸收落锚撞击能量中起重要作用,而撞击塑性变形与锚的类型和撞击速度密切相关。研究成果对海底管道抗锚害设计具有一定的理论指导意义。

Various types of ships anchoring operations in the coastal area are raising the risks of submarine pipeline collision damage. The coupled Euler-Lagrange method （CEL） is used to simulate the process of anchor impact on the submarine pipeline. The nonlinear characteristics of the seabed are simulated using Mohr-Coulomb model. The interactions of the anchor, seabed and pipeline are simulated using the penalty function method. Parameter analysis on the different soil characteristics, anchor dropping speed, anchor size and weight reveal the impact of anchor on the plastic deformation of the pipeline. The results show that the characteristics of the soil buried on the pipe plays an important role in absorbing impact energy of dropped anchor. The impact plastic deformation of pipe is closely related to the anchor type and impact speed. The study results could provide valuable theoretical guidance on the subsea pipeline design related to anchoring damage.