谱载荷下疲劳裂纹扩展随机规律的实验研究

简要介绍了谱载荷下疲劳裂纹扩展试验的理论基础、方法和过程。讨论了各种数据处理方法对参数估计的影响，研究了疲劳裂纹扩展的随机规律。由试验得到的疲劳裂纹扩展试验数据估计了裂纹扩展方程的参数，计算出结构可靠度曲线，通过对试验结果的分析难证了以下结论：以时间为参量的裂纹扩展随机过程模型和以裂纹长度为参量的模型在一定条件下是统一的；数据处理方法的选择与可靠性分析的结果有密切的联系；裂纹扩展寿命受裂纹扩展队机

A Study on the Stochastic Law of Fatigue Crack Propagation under Spectrum Loading

In this paper,the principle and method for the experiment on fatigue crack propagation under spectrum loading are briefly introduced.The stochastic laws of fatigue crack propagation in this case are studied, and the methods for estimating the parameters in crack propagation equations are discussed and compared.Through experiment,it is found that the random process model for fatigue crack growth based on time parameter and its counterpart based on crack length parameter are identical under some conditions, that the results of reliability analysis is affected by the method of parameter estimation and that the estimated fatigue life is affected by the correlative parameters for the stochastic process concerned.