基于雨流修正的船舶宽带疲劳强度分析

Fatigue strength analysis of ship structure based on rain flow correction

船舶结构的交变应力过程呈现宽带谱特点,基于窄带近似的疲劳累积损伤计算结果偏于保守。本文采用频域谱分析直接计算方法,对基于"雨流修正"的宽带高斯应力过程疲劳损伤计算方法进行研究,并通过算例分析给出不同修正方法的船体结构疲劳损伤分析结果。将不同修正方法所得结果与雨流计数方法结果进行比较分析,结果表明Wirsching-Light方法与雨流计数方法结果较为接近。

The alternating stress process of ship structure presents the characteristics of broadband spectrum, and the calculation result of fatigue cumulative damage based on narrow band approximation is conservative. In this paper, the meth-od of frequency spectrum analysis is used to study the fatigue damage calculation of broadband Gauss stress process based on rain flow correction. And an example is given to calculate the fatigue damage results of different correction methods. The fatigue cumulative damage of different correction methods are compared with the results of the rain flow counting method. The results show that the Wirsching-Light method is more close to the results of the rain flow counting method.