中国海洋平台结构抗冰设计关键问题及研究建议

Key issues and suggestions for ice-resistant design of offshore platform structures in China

渤海海域是中国重要的油气产区,但该海域冬季会出现结冰区,因此该区域海洋平台结构的抗冰设计对保障油气增储上产十分重要。渤海海域平台抗冰设计经历了起步、探索、对外合作和独立自主4个发展阶段。本文系统总结了中国渤海地区海洋平台结构抗冰设计面临的关键问题,并给出了相关研究建议。在海冰设计条件方面,受全球气候变化影响,中国海冰冰情整体变弱,现有的海冰区域划分不够精细,部分冰区参数与实际冰情差异较大,且重叠冰设计参数忽视了不同冰区的差异问题,建议基于最新的卫星遥感、业务化预报和实测数据,开展高精细化程度的海冰区域划分研究,并探究工程设计中重叠冰厚度以及强度的合理取值;在结构静态冰载荷计算方法方面,现有计算方法不能适用大径厚比条件,建议基于现场冰力实测和冰水池模型试验,构建新的冰力计算公式,并深入探究多腿结构的遮蔽系数与非同时破坏系数;在动态抗冰设计方法方面,目前尚缺乏明确的可执行规定,尚未建立统一的动冰力模型和疲劳分析算法,建议构建合理的海冰参数概率分布模型,制定平台冰激振动及疲劳设计的设计和评价方法。相关研究成果为中国渤海地区平台结构抗冰设计的优化及下一步研究提供了参考。

Bohai Sea is an important oil and gas producing region in China.However,ice forms in the region during winter,making the ice-resistant design of offshore platform structures crucial for ensuring the increase and storage of oil and gas production.The ice-resistant design of offshore platforms in the Bohai Sea has undergone four developmental stages:initiation,exploration,international cooperation,and independent innovation.The key issues faced in the ice-resistant design of offshore platform structures in the Bohai Sea of China were systematically summarized,and relevant research recommendations were provided.In terms of ice design conditions,due to the impact of global climate change,the overall ice conditions in China have been alleviated.The division of existing ice zones is not detailed enough,and some ice zone parameters differ significantly from actual ice conditions.The design parameters for overlapping ice overlook differences between ice zones.Therefore,it is recommended to conduct high-precision ice zone division studies based on the latest satellite remote sensing,operational forecasts,and measured data and explore reasonable values for overlapping ice thickness and strength in engineering design.In terms of static ice load calculation methods for structures,the existing methods are not applicable under conditions of large diameter-to-thickness ratios.It is thus recommended to establish new ice force formulas based on on-site ice force measurements and ice tank model tests and thoroughly investigate the shielding coefficient and non-simultaneous failure coefficient of multi-leg structures.In terms of dynamic ice-resistant design methods,there is currently a lack of clear executable regulations,and a unified dynamic ice force model and fatigue analysis algorithm have not been established.Therefore,it is suggested to construct a reasonable probabilistic distribution model of ice parameters and formulate design and evaluation methods for ice-induced platform vibration and fatigue design.The related research findings provide references for the optimization of the ice-resistant design of platform structures in the Bohai Sea of China and point out the direction of future research.