自升式钻井平台的抗冰性能评价

自升式钻井平台属于典型的柔性结构。由于冰与柔性抗冰结构相互作用的复杂性,长期以来尚未形成基于动冰力响应分析的结构设计。结构抗冰设计中大都是从极端荷载出发,只考虑最大静冰力或最大倾覆力矩是否能推倒平台。基于对渤海辽东湾柔性抗冰平台的多年监测,发现强烈的冰激振动引起平台管节点疲劳失效、上部设施的非正常运行、作业人员不舒适等问题的风险性要远大于极端静冰荷载下结构的整体安全问题。文中基于多年现场冰与结构作用观测及冰荷载的研究成果,提出了柔性抗冰结构设计中应考虑的主要失效模式及评价方法。最后,以渤海某典型自升式钻井平台为例,对其抗冰性能进行评价。该文的研究可为寒区自升式平台的抗冰概念设计提供合理依据。

Structural ice-resistant performance evaluation of jack-up drilling platforms

The jack-up drilling platforms belong to the typical flexible structures. As the complexity of the interactions between the ice and structures, the design code of the flexible ice-resistant structures is not based on the dynamic response analysis. Current design codes for ice-resist offshore structures mainly deal with the extreme force, not the dynamic ice loads. Based on the field monitoring data of ice-resist platforms in Bohai Liaodong Gulf, the significant ice-induced vibration not only causes significant cyclical stress of tube node but also great acceleration response, which can endanger the pipeline systems on the platform and discomfort the crew members. The risks induced by ice vibrations are more serious than the extreme static ice load. In this paper, based on the field monitoring and ice loads research, the main failure modes and evaluation methods for the flexible ice-resistant structure design are provided. Finally, the ice-resis-tant performance is analyzed by taking a jack-up platform in Bohai Sea as an example. This study providesa reasonable basis for the ice-resist concept design of the jack-up platforms in the cold regions.