撞击船艏刚度对船体结构碰撞性能影响

  目的  基于非线性有限元方法的船体结构碰撞数值仿真分析，其计算精度受到材料本构关系与失效定义、接触定义和单元网格尺寸等仿真控制参数的影响，且相关参数定义还需经过模型试验校准。为了充分模拟实船舷侧板架结构受到碰撞冲击时主要吸能构件的响应特点，使数值仿真模型试验校准充分有效，  方法  采用接近实船的结构构件尺寸和高强度低合金钢材料设计制造模型结构，开展舷侧板架结构落锤冲击试验。通过试验记录，分析在碰撞冲击载荷作用下结构损伤变形的机理和模式。在此基础上，对碰撞冲击后的舷侧板架结构损伤变形进行数值仿真分析，并对有限元仿真结果与模型试验结果进行对比。  结果  结果表明：数值仿真得到的板架结构损伤变形模式与模型试验结果较为一致，较好地模拟了外板的撕裂破坏、膜拉伸变形和骨材断裂以及失稳；冲击加速度曲线也与试验有较好的一致性。  结论  研究结果可为水面舰船结构碰撞仿真及解析计算方法提供验证依据。

Behavior of a double hull in a variety of stranding or collision scenarios

  Objectives   The numerical simulation analysis accuracy of hull structure under impact test, based on nonlinear finite element method(FEM), is affected by a series of simulation control parameters such as material constitution and failure definition, contact definition, element mesh size, etc., and the definitions of the aforementioned parameters require to be calibrated through model tests. In order to fully simulate the response characteristics of main energy-absorbing members on the side grillage structure of the real ship during the impact test, and make the calibration of the numerical simulation model test effective,  Methods   a model structure with structural member dimensions close to the real ship and made of high-strength low alloy steel material is used, and a drop weight impact test of side grillage structure is carried out here. Then according to the resulting test records, we analyze the mechanism and mode of damage and deformation of the grillage under impact load, then accordingly conduct the numerical simulation analysis, and compare the finite element simulation results with the model test results.  Results  The results show that the damage and deformation mode obtained from the numerical simulation is consistent with the model test result, and tearing failure, membrane tensile deformation, frame fracture and instability of shell plate are well simulated, and the impact acceleration curve is in good agreement with the test.  Conclusions   The results herein can provide a verification reference for the impact simulation and analytical calculation of surface ship structure.