摘要
基于线性累积损伤原理的船体结构疲劳强度评估方法已经在各种民船结构的设计规范中得到了广泛的应用,但其中疲劳载荷的计算方法和主要参数差别较大,导致结构疲劳寿命的评估结果具有一定的分散性。文中利用长期疲劳应力范围的Weibull分布和S-N曲线方法给出的结构疲劳寿命谱分析计算公式,通过理论分析和数值计算,分析了对结构疲劳损伤贡献率最大的长期应力范围所对应的超越概率水平,以及S-N曲线反斜率对该超越概率水平的影响。研究了不同超越概率水平下形状参数对结构疲劳寿命的影响,讨论了疲劳寿命对超越概率水平、形状参数和S-N曲线反斜率的敏感性。文中给出的一些结论对国际船级社协会正在进行的共同油船和散货船结构规范协调性研究具有参考价值。
Rules and regulations for fatigue life assessment based on linear cumulative damage prin- ciple were widely used in ship and offshore structural desigu.But the fatigue loading estimation pro- cesses and main parameters given in them are not consistent,and the resultant fatigue lives are quite dispersed. In this paper, structural fatigue life estimation expression is presented based on Weibull distribution of long-term fatigue stress range and S-N curve.With theoretical analysis and numerical simulation, exceeding probability corresponding to maximum contribution of the long-term stress ranges to structural fatigue damage is analyzed,which is affected by reverse slope of S-N curve. The effects of Weibull shape parameter on structural fatigue life are investigated under various exceed- ing probabilities.The sensitivities of the structural fatigue life to exceeding probability, shape param- eter and reverse slope are discussed. Some conclusions are drawn, which might be valuable for un- dergoing harmonization of common structural rules （HCSR） for bulk carriers and oil tankers.
出处
《船舶力学》
EI
北大核心
2012年第6期658-667,共10页
Journal of Ship Mechanics
关键词
疲劳寿命
疲劳载荷
形状参数
超越概率
S-N曲线
fatigue life
fatigue loading
shape parameter
exceeding probability
S-N curve
