基于VUMAT的海洋结构物撞冰行为数值仿真

Numerical Simulation of Marine Structure Colliding with Sea Ice Based on VUMAT

对海洋结构物撞冰行为和冰载荷特性进行研究。基于ABAQUS通用有限元软件平台开发理想弹塑性冰材料VUMAT用户子程序;根据Tsai-Wu屈服准则和经验失效准则,采用完全隐式向后欧拉回映算法实现冰材料应力和应变的更新,并通过单个单元的压缩和拉伸试验验证该子程序的可行性。采用已开发的冰材料VUMAT子程序模拟刚性直立圆柱结构以不同速度撞击平整冰排,研究海冰的损伤过程,并分析碰撞速度对结构物承受冰载荷的影响。模拟刚性勺型破冰艏冲撞式破冰场景,并研究冰层厚度对冰载荷的影响。

The research on the collision behavior between marine structures and sea ice as well as ice load properties is carried out.A VUMAT user subroutine of perfectly elastic-plastic ice material is developed based on the finite element software platform ABAQUS,and in line with Tsai-Wu yield criterion and empirical failure criterion,the stress and strain of ice material are updated with fully implicit backward Euler reflection algorithm.And the feasibility of the VUMAT user subroutine is validated by single element compression and tension simulation test.With this VUMAT subroutine of the developed ice material,the process of a rigid vertical cylindrical structure colliding with level ice at different velocity is simulated to study the process of ice damage and to analysis how collision velocity influences ice loads applied on the cylindrical structure.The crash-icebreaking scenario of a rigid spoon-shaped icebreaking bow is simulated and the influence of thickness of level ice on ice loads is then discussed.