破损舰体结构疲劳裂纹扩展及剩余寿命研究

Fatigue crack propagation and residual life prediction of damaged ship structures

采用预制缺口的907A钢平板结构试样进行拉伸疲劳载荷试验,得到了拉伸疲劳载荷作用下平板结构破口裂纹扩展规律。采用奇异单元法计算了相应试件的裂纹尖端应力强度因子,利用Paris准则得出裂纹扩展速率与应力强度因子的关系式。提出了破损舰体结构的疲劳裂纹扩展模型,用于估算破损舰船结构在波浪中航行时的裂纹扩展分析和剩余寿命预报。通过某型舰算例验证了文中试验计算方法的合理性。

Using 907A steel plate specimens with V type gap,the tensile fatigue test was completed and the rule of fatigue crack propagation was researched.Based on singular element method stress intensity factor of plate specimens was calculated,the relation between crack propagation rate and △K was given according to Paris rule.The fatigue crack propagation model was offered for analyzing and predicting crack propagation situation and the remaining life assessment of damaged warship in waves.The reasonability of the method was demonstrated by the calculation example of some warship.