中文摘要：

充分考虑平台系统在复杂海况下的耦合非线性效应，分别采用反映海床吸力效应的线性滞后模型和传统线性海床模型模拟立管触地区域和海床的相互作用，对深海钢悬链线立管进行非线性时域模拟，根据预报的触地点响应采用确定性方法计算应力参数。根据基于S-N曲线及Miner准则建立极限状态方程，采用一阶可靠度方法研究触地点的疲劳可靠度，结果表明，与传统模型相比，线性滞后模型得到触地点在低应力范围的循环次数较多而在较高应力范围区域的循环次数较少，因而具有较高的可靠度指标。文中的立管疲劳可靠性分析将平台/系泊索/立管作为一个统一整体并包括海床对立管的吸力效应，有助于提高钢悬链线立管的疲劳可靠性设计的精度。

英文摘要：

Taking platform system coupled nonlinear effect in complicated sea state into account, and using linear hysteretic seabed model and traditional seabed model to simulate riser-soil interaction respectively, nonlinear time domain simulation is carried out for steel catenary riser, and deterministic method is used to calculate stress parameter through predicting touch-down point’s （TDP’s） response. According to the state functions based on S-N curve and Miner’s rule, the TDP’s fatigue reliability is studied through first order reliability method （FORM）, and the result shows that the linear hysteretic model obtains more cycles in low stress range than traditional linear model, but less cycles in high range, which result in higher reliability index. In this paper, platform/mooring/riser is considered as a whole and the seabed suction effect is included, so the present study is helpful to improve the accuracy of the fatigue reliability design of SCRs.