Abstract: The variability of dynamic fatigue load varied with time during the life cycle of offshore platform was divided into two parts of long-term variability and short-term variability of fatigue load.The long-term variability was described by Poisson model,and the short-term variability was described by continuous smooth random process.A new modeling method for the environment loads in the life cycle of platform was proposed.A new dynamic reliability analysis method for offshore platform considering fatigue failure was developed.The applied example illustrated the validation of the proposed method.

Key words: offshore platform, dynamic fatigue, load, reliability analysis, fatigue failure, modeling method

摘要： 为了实现海洋结构的全寿命周期管理,将平台寿命周期内的动态疲劳载荷随时间的变异性分为载荷的长期变异性和短期变异性两种趋势.载荷长期变异用泊松模型描述,短期变异用连续平稳随机过程描述.提出了一种海洋平台寿命周期内的环境载荷建模的新方法,并给出了考虑疲劳失效的动态疲劳可靠性的分析方法,实现了平台寿命周期内的动态疲劳可靠度计算.通过对南海某平台的实例分析,验证了该方法的可行性.

关键词: 海洋平台, 动态疲劳, 载荷, 可靠性分析, 疲劳失效, 建模方法