半潜平台疲劳波浪载荷的不确定性研究

Uncertainty analysis of fatigue wave loading for semi-submersible platform

为了评估疲劳载荷计算过程中波浪载荷的不确定性,首先给出了考虑不确定影响因素的S-N曲线方法下结构的疲劳寿命评估表达式,然后建立了平均跨零周期、海况发生概率和浪向等引起的波浪载荷不确定性的评估方法和公式。重点对西北太平洋和中国南海的海况进行了分析,定量统计回归出了西北太平洋的波浪周期修正公式,以及中国南海不同季节海况和浪向分布规律对某半潜平台波浪载荷和疲劳寿命的影响因子。

For assessing the uncertainties of wave loading during the calculation of fatigue loading, the expression of structural fatigue life is proposed by S-N curve method after considering the influences of uncertainty, The assessing methods and equations of wave loading uncertainty including mean rence of sea states and wave direction are built.The correcting formula of period tistical regression after analyzing the sea states in Northwest Pacific and South while,the influences of fatigue life caused by sea states in different seasons and direction are investigated for semisubmersible platform. crossing zero period, occuris given quantitatively by staChina Sea especially; meandistribution principle of wavedirection are investigated for semisubmersible platform.