【作者】 于佰杰；

【导师】 武文华；

【作者基本信息】 大连理工大学 ， 计算力学， 2007， 硕士

【摘要】 随着能源需求量的日益增加，海洋采油平台的设计尤为重要，其中海冰对海洋平台的威胁成为科研人员关注的课题。为避免冰激振动，以显示动力分析软件LS-DYNA为工具，模拟了海冰和海洋平台锥体抗冰结构相互作用的破碎过程。通过断裂过程的模拟得到了海冰弯曲断裂过程，模拟结果和现场观测一致。海冰的破碎长度符合实测结果。同时模拟结果给出了冰荷载时程曲线，呈现与实测结果一致的三角形脉冲形式。模拟得到了平台上部结构振动的位移和加速度响应信息。通过数值模拟对海冰断裂过程和冰荷载的影响因素进行分析。首先分析了冰锥接触宽度对破坏模式和断裂长度的影响，结果显示冰锥接触宽度不是破坏模式转变的主要因素，对断裂长度的影响不大。同时分析了锥体角度、海冰厚度、弹性模量和海冰速度对海冰断裂行为的影响程度。针对科研人员关心的冰锥交界处的破碎情况进行了分析，结果表明在冰锥交界处没有发生像海冰与直立结构相互作用一样的挤压破碎情况，海冰仍然表现为弯曲断裂，但冰荷载峰值略高。文章最后一部分对海冰和渤海JZ20-2海域的MUQ中北和NW北高两个现役海洋平台的相互作用过程进行模拟。结果显示出与实测相近的海冰断裂情况、海冰的断裂长度、冰荷载以及平台振动信息，为海洋平台抗冰结构设计提供参考。更多还原

【Abstract】 With the increase of energy requirement, it presents the essential requirement from the design of offshore structures. Many researchers have devoted their efforts to the interactions between sea ice and offshore platform. In order to avoiding ice-induced vibration, explicit software LS-DYNA is used to simulate the failure process caused by sea ice impacted with conical platform.Simulate results indicates that the obtained bending process is consistent with in-situ test. The ice break length belongs to the typical range of in-situ measurements. Ice force exhibits the metrical triangle shape. The simulated results also give the vibration information in platform, such as displacement and acceleration history etc.The parametric analyses which affect ice failure process and ice force are performed. The ice-cone contact width is not a sensitive factor to the transformation of ice failure mode and break length. The effects of conical angle, ice thickness, elastic modulus and ice velocity also are considered. The simulate result also shows that there is no compress failure process at up-down conical intersection. But the peak force is high compare with other contact positions.The simulations of two platforms, Bohai JZ20-2 MUQ and NW, are performed in the fifth section, ice failure process, break length, ice force and vibration are consistent with true field experiments. The present results provide the reference to platform design.更多还原