逐次累积裂纹扩展计算的循环计数方法

给出一种疲劳损伤的累积方法,用于随机谱载下的裂纹扩展模型计算,该方法既能充分计及疲劳裂纹尖端材料的累积损伤作用,又提供了在裂纹扩展模型计算中实时考虑加载序列影响的可能性。本方法可应用于各类疲劳寿命及裂纹增长分析预测模型的计算,克服了以往方法中不能维持原有峰谷序列的缺陷,使模型计算过程更趋合理和符合实际的损伤机制,从而便于各种模型的发展、改进和评价。

A CYCLE COUNTING METHOD FOR CYCLE BY CYCLE CRACK GROWTH ANALYSIS

A random fatigue load cycle counting method is suggested for cycle by cycle calculation of crack growth analysis. This method makes it possible to consider exactly the effect of load sequence in crack growth model calculation. As a tool of crack growth model predictions, it can be used in the analyses of various types of models and can solve the problem in previous counting method, with which the load sequence can't be exactly maintained, and some peak or valley position will be changed and therefore affects the retardation calculation. With the proposed counting method, crack growth model calculation will be more reasonable and properly fit the actual damage mechanism, which is significant for various crack analysis models to be developed, improved and evaluated.