基于谱分析的FPSB疲劳寿命评估和优化

FPSB是一种新型深远海大型浮式结构物，长期承受交变波浪载荷作用，易发生疲劳而使得结构失效。本文以一艘FPSB为研究对象，使用谱分析法对其疲劳寿命进行了评估。首先建立水动力模型计算波浪载荷响应算子RAO，建立整船结构模型计算船体结构响应，随后选取典型节点建立子模型以得到精确的热点应力传递函数，采用北大西洋海况和P-M海浪谱，基于S-N曲线和线性累积损伤准则对典型节点的疲劳寿命进行计算分析。根据疲劳评估结果，对易损节点进行基于疲劳性能的结构优化，以提高节点形式的合理性及结构安全可靠性。

Fatigue Life Assessment and Optimization of FPSB Based on Spectrum Analysis

FPSB (Floating Process and Supply Base) is a new type floating offshore which is subjected with alternate wave load during its service life. It is easy to take place structural collapse due to fatigue failure. A typical FPSB is considered as the objective and spectrum analysis is adopted to evaluate its fatigue life in the present research. Hydrodynamic calculation model is generated to calculate the RAOs firstly. Whole structural model is used to obtain the structural stress distribution. Then, sub-structural model of typical joint is generated to calculate the stress transfer function of hot spot. The wave scatter diagram of North Atlantic and Pierson-Moskowitz spectrum are adopted to calculate the fatigue life of the typical joint based on S-N curves and linear cumulative damage criteria. Finally, the structural optimization on vulnerable joint is performed according to the fatigue assessment results in order to achieve the reasonable joint structure and improve the structural safety.