提出一种用于估计随机波浪载荷作用下自升式海洋平台极值响应的参数化方法.该方法采用移位广义对数正态分布模型近似计算平台随机响应的极值分布，由紧邻分布尾部的两个支撑点及其超越概率估计模型参数，从而减少估计极值响应分布尾部所需的响应样本容量.将所提出方法用于某实际平台的极值响应分析的结果表明，该方法具有数值精度高和计算费用小的优点，适用于随机波浪载荷作用下自升式平台的可靠性及风险评估.
For estimating the extreme response of the jack-up platform, a parametric method under the action of random wave loads is developed. The method approximates the extreme distribution of the stochastic response of the platform by using the shifted generalized lognormal distribution model. The model parameters are estimated by two supporting points and their exceeding probability in the adjacent tail distribution such that the size of the needed samples is reduced significantly. The extreme response analysis of a real platform shows that the proposed method has enough high numerical accuracy and needs relatively few computational costs, which is suitable for the reliability and risk assessment of the jack up platform under the action of random wave loads.
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