中文摘要：

由于水深的增加，在风浪流载荷作用下，采用分段组合锚泊系统定位，平台移动范围可能超过安全作业区域范围，极易导致钻井隔水管破坏，从而影响钻井平台正常作业。采用分段组合锚泊设计系统，考虑了钻井平台与锚泊的耦合作用，应用AQWA软件建立了981深水半潜式平台三维水动力模型。在此基础上，以南海风、浪、流载荷为背景，在不同锚泊系统顶部倾角情况下，分析锚泊线的张力和平台的偏移量。分析结果表明，在百年一遇的极端载荷下，半潜式钻井装置的锚泊线安全系数为1.73，大于API标准1．67且锚泊线张力值小于破断载荷，平台在水平面的最大偏移值超过了正常作业区域，但还在最大连接工况10％范围及最大自存工况范围内。在此锚泊系统的作用下，钻井装置在1500m水深时能在百年一遇的极端天气中生存，其锚泊系统的设计组合合理，满足锚泊线强度及平台定位安全的要求。

英文摘要：

With increase of water depth, platforms positioned by using sectional combined anchoring may move beyond limit for safe operations under loads of winds, waves and currents. Such movements may system damage riser and consequently impact normal operation of the drilling platform. The sectional combined anchoring system is designed with consideration of coupling between the drilling platform and the anchoring system. A 3 D hydrodynamic model has been established for the 981 Deep-water Semi-submersible Platform by using software AQWA. With the model, tension of the anchoring line and offsets of the platform can be analyzed for different top inclinations of the anchoring system with winds, waves and currents of the South China See as the background. Analysis results show that safety factor for anchoring lines of semi-submersible drilling facilities is 1.73 under extreme loading condi- tions. The safety factor is higher than the 1.67 of API. In addition, tensions of anchoring lines are lower than the failure loads. Under such circumstances, maximum horizontal offsets of the platform may go beyond normal working area, but still within 10% around the maximum connection extent and the maximum survival extent. With the an- choring system, drilling facilities may survive rough weather conditions expected once for every 100 years at the water depth of 1 500 m. With rational design and combination, the anchoring system may satisfy requirements relat- ed to strength of the mooring line and positioning of the platform.