针对目前船舶疲劳强度评估问题，频域谱分析法将应力范围服从Rayleigh窄带分布，造成结果偏保守。而时域法则计算时间过长，无法满足快速预估需求。本文以频域谱分析法为基础，提出一种适用于宽带随机过程的改进谱分析法，并以实船为算例进行计算分析。结果表明，基于改进谱分析法的疲劳计算结果与精确解差距较小，可以提供一个相对可靠的船舶疲劳损伤结果。新方法对解决宽带随机过程下的船舶疲劳评估问题有一定参考意义。
Aiming at the problem that the assessment of fatigue strength, the results are conservative based on spectral analysis method. Because the range of stress is treated as Rayleigh’s model, Rayleigh’s model is a narrow model. The time of calculation based on time-domain analysis method is too long, this method is unable to meet the requirement of the fast assessment. This paper gives improved spectral analysis method of fatigue assessment suitable for wide-band random process based on spectral analysis method. Then Taking a ship as an example to analyze. The results show that: the result of calculation based on improved spectral analysis method is close to the accurate solution. This method can provide a relatively reliable result of assessment for fatigue strength. The new method has reference significance for assessment of fatigue strength under wide-band random process.
2022,44(2): 48-52 收稿日期：2021-04-26
DOI：10.3404/j.issn.1672-7649.2022.02.010
分类号：U661.43
基金项目：南通市市级科技计划项目(JCZ20183)；江苏省高等学校自然科学研究项目(18KJD580003)
作者简介：周陈炎(1993-)，男，硕士，讲师，研究方向为船舶结构强度计算
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