【摘要】 文章研究了深水半潜式平台结构疲劳裂纹扩展寿命,首先对疲劳裂纹扩展模型和平台结构疲劳寿命计算方法进行了分析,通过对不同工况下深水半潜式平台结构的强度分析和整体疲劳寿命的估算,确定平台疲劳关键部位。然后对疲劳关键部位进行了应力响应分析,得到等效应力幅值,采用了考虑门槛值、应力比等因素影响的疲劳裂纹扩展率单一曲线模型,计算了各疲劳关键部位的疲劳寿命。结果表明:不同工况下关键部位的疲劳裂纹扩展寿命可以满足设计要求,基于裂纹扩展的疲劳分析方法可用于深水半潜式平台结构的疲劳寿命分析。更多还原

【Abstract】 This paper studies the fatigue crack propagation assessment for the deepwater semi-submersible platform. The model of fatigue crack propagation and the calculation method of fatigue life for platform structures are introduced. The global strength and fatigue lives of the platform in different sea-state are analyzed to determine the fatigue key parts. Then, the stress responses of the fatigue key parts are analyzed to gain the equivalent stress amplitude. The fatigue lives of key parts are calculated using the unique crack growth rate curve model which considers the affect of the threshold, stress ratio and other factors. The results show that the fatigue crack propagation lives of key parts in different sea-state can meet the design requirements; the method of crack growth-based fatigue analysis is suitable for the fatigue assessment of the platform.更多还原