Abstract Floating glacial ice features of various sizes pose a substantial threat to the structural integrity of offshore structures in ice-prone regions. Relatively small ice feathers, e.g., bergy bits and growlers, are a major concern because they are more difficult to detect by marine radars and perform concurrent ice management operations, especially in extreme sea states. This two-part companion paper aims to assess potential loads of accidental ice actions that are exerted on an offshore semi-submersible platform and the consequences of these actions. Paper I investigates the probability distributions of glacial ice impact velocities and the associated impact heights under different sea states. Given the critical impact energy identified from Paper I, Paper II investigates ice crushing and structural damage during glacial ice impacts in accidental limit states (ALS) and ice-structure interactions. Three different approaches, i.e., the integrated approach, weakly coupled approach and fully coupled approach, are employed. The methods are based on different coupling strategies between ice and the structure and are used to identify the critical local ice sharpness for stiffened panels of the platform column, which causes maximum structural damage given an energy demand. The accuracy of the simulation results, calculation efficiency and scope of application using the three approaches are compared and discussed. With the identified critical sharpness of the ice model, numerical simulations are performed to impact various locations of the platform column. Apart from scenarios with head-on ice impacts, several oblique impact scenarios are simulated, where the glacial ice feature slides along the contact plane with different initial indentations of the panel. The results are discussed with respect to the resistance and energy absorption of the ice and structure and ice-structure interactions.

中文翻译：

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冰川冰影响：第二部分：意外极限状态 (ALS) 中的损伤评估和冰结构相互作用

摘要 各种大小的浮冰特征对易冰区近海结构的结构完整性构成重大威胁。相对较小的冰羽，例如冰屑和咆哮者，是一个主要问题，因为它们更难以被海洋雷达探测到并执行并行的冰管理操作，尤其是在极端海况下。这篇由两部分组成的配套文件旨在评估施加在海上半潜式平台上的意外冰作用的潜在载荷以及这些作用的后果。论文 I 研究了不同海况下冰川冰撞击速度和相关撞击高度的概率分布。鉴于论文 I 中确定的临界冲击能量，论文 II 研究了在意外极限状态 (ALS) 和冰结构相互作用下的冰川冰撞击过程中的冰破碎和结构损坏。采用了三种不同的方法，即集成方法、弱耦合方法和完全耦合方法。这些方法基于冰和结构之间的不同耦合策略，用于识别平台柱加筋板的临界局部冰锐度，在给定能量需求的情况下，这会导致最大的结构损坏。对三种方法的仿真结果的准确性、计算效率和适用范围进行了比较和讨论。确定冰模型的临界锐度后，进行数值模拟以影响平台柱的各个位置。除了迎面冰面撞击的场景，模拟了几种斜向撞击场景，其中冰川冰特征沿着接触平面滑动，具有不同的面板初始压痕。讨论了冰的阻力和能量吸收以及结构和冰结构相互作用的结果。