中文摘要：

自升式平台在海洋石油开发中被广泛应用,为保障平台在各类海况中正常工作,其结构强度是安全评估的重要依据.以渤海海区的自然环境条件为设计背景,考虑风载荷、流载荷、冰载荷和波浪载荷等环境载荷,以及载荷沿横向、纵向和斜向作用时,对平台的结构强度进行有限元分析,计算平台桩腿和主体结构在不同工况下的应力与变形,表明平台主体和桩腿上最大应力发生在风冰载荷横向作用的工况;在横向外载荷的作用下,桩腿靠近泥面的部分和固桩室附近受到的应力大,应进行局部加强;平台主体部分局部载荷较大的甲板区域也应加强;纵向构件必须满足强度要求才能确保平台承载的最大应力.综合计算结果,为该平台结构的优化设计和安全评估提供参考.

英文摘要：

The Jack-up platforms have wide applications in offshore oil exploration. In order to guarantee its normal operation under various sea conditions, the structural strength is an important basis for the safety assessment. Taking the environmental conditions in Bohai area as the design background, the wind, current, ice and wave environmental loads are considered. The structural strength analyses based on finite element method are performed for loads acting transversely, longitudinally and obliquely. The stress and deformation of the platform legs and main structures under various loading conditions are calculated, which show that the maximum stress occurs under transversal wind and ice loading condition. And under the transversal outer load, the leg section near the mud surface and the spud can area will be under high stress and require local strengthening. The deck areas of the main platform with big local load should also be strengthened. The longitudinal components must meet the strength requirements to ensure the platform to bear the maximum stress. Based on the calculation results, some references are provided for the structural design optimization and safety assessment of this type of platforms.