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 method 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.
2018,40(8): 23-26 收稿日期:2018-03-11
DOI:10.3404/j.issn.1672-7649.2018.08.004
分类号:U661.4
基金项目:国家重点研发计划重点专项资助项目(2016YFC0301500);海洋工程国家重点实验室开放基金资助项目(1513);中央高校基本科研业务费专项资金资助项目(3132016346,3132018206,3132018201);辽宁省博士启动基金资助项目(201601070)
作者简介:甄春博(1982-),男,博士,讲师,研究方向为船体结构疲劳。
参考文献:
[1] 胡毓仁, 李典庆, 陈伯真. 船舶与海洋工程结构疲劳可靠性分析[M]. 哈尔滨:哈尔滨工程大学出版社, 2010.
[2] DNV, Classification Note No. 30. 7:Fatigue Assessment of Ship Structure, Det Norske Veritas, 2010.
[3] ABS, Guidance Notes on Spectral-based Fatigue Analysis for Vessels, American Bureau of Shipping, 2004.
[4] 中国船级社. 船体结构疲劳强度指南[S]. 北京:人民交通出版社, 2007
[5] WIRSCHING, P. H. & LIGHT, M. C. Fatigue under wide band random stresses[J]. Journal of the structural Division, ASCE (American Society of Civil Engineers). 1980, 106(7):1593-1607.
[6] ORTIZ CHEN. Fatigue damage prediction for stationary wide band stresses[C]//5th International Conference on Applications of Statistics and Probability in Civil Engineering (ICASP), 1987, Vancouver, BC, Canada.
[7] CHAUDHURY G K, DOVER W D. Fatigue analysis of offshore platform subject to sea wave loadings[J]. Int J Fatigue, 1985, 7:13-19.
[8] LUTES, L, LARSON, M. L. Improved spectral method for variable amplitude fatigue prediction[J]. Journal of the Structural Division. ASCE, 1990, 116:1149-1164.
[9] 李晓飞, 胡毓仁. 宽带波浪载荷下海洋结构物内应力范围及疲劳损伤分析[J]. 海洋工程, 2008, 04:35-38.
[10] GAO Z, MOAN T. Frequency-domain fatigue analysis of wide-band stationary Gaussian processes using a trimodal spectral formulation. International Journal of Fatigue, 2008, 30:1994-1955.