海洋环境复杂多变，海上结构物需长期承受随机波浪引起的交变载荷，极易产生疲劳破坏。本文以某海上大尺度异型镂空浮体为研究对象，通过计算分析找出了异形浮体结构容易产生疲劳破坏的位置。为使结构疲劳谱分析计算结果更加准确，本文提出一种数值规则波模拟法，用来计算浮体结构在工作时应力的传递函数。在此基础上，分别采用基于热点应力与名义应力的谱分析方法计算了浮体的疲劳寿命。结果显示，基于热点应力法得到的结构疲劳寿命略低于基于名义应力法得到的疲劳分析结果，更偏保守。以上研究结果可为大型海上浮式结构的设计提供参考。
The marine environment is complex and changeable, and offshore structures need to bear the alternating load caused by random waves for a long time, which is very easy to cause fatigue damage. In this paper, a large-scale special-shaped hollow floating structure is taken as the research object, and the location where the structure is prone to fatigue failure is found through calculation and analysis. In order to make the results of structural fatigue spectrum analysis more accurate, a numerical regular wave simulation method is proposed to calculate the transfer function of structural stress. On this basis, the fatigue life of the floating structure is calculated by using the spectrum analysis method based on hot spot stress and nominal stress respectively. The results show that the fatigue life of the structure based on hot spot stress method is slightly lower than that based on nominal stress method. The above research results can provide reference for the design of large offshore floating structures.
2024,46(9): 99-105 收稿日期：2023-06-21
DOI：10.3404/j.issn.1672-7649.2024.09.017
分类号：U66K
作者简介：张书友（1997 – ），男，硕士研究生，研究方向为环境载荷与结构分析
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