OMNI-Max锚初始贯入行为的研究

Study on the Initial Penetration of OMNI-Max Anchors

深水锚是深水系泊系统的核心组成部分,而重力贯入锚是深水锚最新发展型式,具有其他深水锚难以企及的综合优势,尤其是OMNI-Max锚具备可抵御灾害条件的特殊能力。本文采用大变形有限元分析技术耦合的欧拉-拉格朗日(CEL)法模拟OMNI-Max锚在海床土中的初始贯入行为,考虑了应变率与应变软化效应和水流拖曳力,并合理地处理了锚-土界面摩擦,研究了锚的运动行为、土体流动机理、土体破坏模式及土体强度响应。通过现场试验数据进行对比,验证了数值模型的可靠性。基于本文所建立模型的分析结果,加深对OMNI-Max锚安装过程的认识,以期为工程应用提供有益的建议。

Deepwater anchors are key elements in a deepwater mooring system. Gravity installed anchors are the latest developments of deepwater anchors, which have more comprehensive advantages than the conventional anchors. Especially, the OMNI-Max anchor has the special ability to avoid the catastrophe. A large deformation finite element analysis using a Coupled Eulerian-Lagrangian （CEL） approach was performed to simulate the initial penetration of OMNI-Max anchors in the seabed, considering the effects of soil strain rate, soil strain-softening and hydrodynamic drag, with the anchor-soil friction described appropriately. The kinematic behaviors of the anchor, flow mechanism and failure pattern of the soil, and response of soil strength were studied. The numerical framework was verified by the comparision with the field data of OMNI-Max anchors. Based on the calculated results, the installtion of OMNI-Max anchors are understood thoroughly, which will provide useful suggestions for the engineering practice.