【作者】 宋斌；

【导师】 付世晓；

【作者基本信息】 上海交通大学 ， 船舶与海洋结构物设计制造， 2012， 硕士

【摘要】 在南海未来的油气开发区域建立超大型浮式海上基地(VLFOB),将其作为存放周边油气田开发所需物资的海上补给基地和中转站,并能满足深水作业船风暴期间临时停靠的需求,这样就能解决由于南海油气勘探开发涉及的海域很广及其恶劣气候给南海油气勘探开发带来的诸多困难。超大型浮式海上基地是由八个单体模块组合而成的结构,模块间需要采用连接构件进行连接,连接构件将是危及其安全性的一个重要因素。本文针对VLFOB这一新型的超大型浮式结构物设计概念,对其连接件刚度和载荷特性进行了研究。首先研究了VLFOB连接件的刚度对其固有频率影响,利用有限元方法计算得到不同连接件刚度条件下系统的固有频率,与南海一年一遇海况、十年一遇海况、百年一遇海况和千年一遇海况的波浪谱对比后确定了连接件的拉伸刚度应该大于10000MN才能有效地防止共振,减少连接件的动力响应。然后通过数值计算和模型试验两种方法研究了单体间的连接面与浪向呈不同夹角时,连接面三个方向载荷的变化趋势。研究得出连接面径向载荷和轴向载荷受连接面与浪向夹角的影响明显,而垂向载荷受连接面与浪向夹角影响较小。综合分析连接面与浪向不同夹角时连接面三个方向载荷变化趋势得出VLFOB各个连接面与浪向呈0°至30°的夹角时承受的轴向载荷较大。通过研究在南海一年一遇、百年一遇和千年一遇海况下VLFOB连接面三个方向的极限载荷,得出在各海况下VLFOB连接面轴向载荷极值最大,径向载荷极值其次,垂向载荷极值最小。各海况下连接面载荷极值均是连接面与浪向夹角为0°时的轴向载荷,试验测得在南海一年一遇海况下29066.0t,在百年一遇海况下96712.2t。更多还原

【Abstract】 A new concept of Very Large Floating Offshore Base (VLFOB) is proposed for the application in deepwater oil and gas exploration and production in the South China Sea. The long distance from mainland and the abominable weather make the supply of materials difficult and the workers and facilities unsafe, the VLFOB can solve these problems because it will be used as a supply base and a harbor for the deep ocean work boats.The VLFOB is constructed by 8 single modules and the connectors between the modules are one of the key factors about the safty of the VLFOB. In this paper the loads on the connectors of the VLFOB are studied.The natural frequencies of the VLFOB with different connector stiffness are calculated by FEM method, and the corresponding results are analyzed by comparing them with the wave spectrum of 1-year,10-year,100-year and 1000-year environments in South China Sea. The results show that the VLFOB can avoid sympathetic vibration effectively by adjusting the stiffness of the connectors to be larger than 10000MN.The loads acted on the connector are calculated by numerical computation method and measured through the model tests in the ocean basin, the results show that the axial load and radial load on the connectors are closely related to the angle between connectors and the wave, the vertical load is not so closely. Besides, When the angle between connectors and the waves is between 0 degree and 30 degree, the axial load is very large.The axial load when the angle between connector and wave is 0 degree is the largest in 1-year, 100-year and 1000-year environments in South China Sea,and it is 29066t in 1-year environment and 96712.2t in 100-year environment更多还原