随机应力过程应力峰概率密度函数分析

Peak probability density function of stochastic stress process

利用平稳随机过程峰值的概率分析,给出了计算应力峰概率密度函数的公式。通过研究随机过程峰值分布的规律,提出了由随机过程的功率谱密度函数来分析随机过程峰值概率密度函数的新方法。根据S.O.Rice对随机过程峰的一维概率分布的研究方法,扩展到对随机过程峰的联合概率密度的分析。文中分析了一个特殊的例子——零均值的平稳高斯随机应力过程,得到了很好的结果,为进一步进行疲劳损伤及寿命研究打下了基础。

Based on the peak distribution analysis of stationary stochastic process, the general expression for the peak probability density function of a stress process is described. A method for analyzing distribution of peaks of stochastic process is proposed by studying the distribution of peaks in a stochastic process. In the method, the probability density function of a stochastic process is described from the spectral density function of the stochastic process. S. O. Rice gave the probability distribution of a single peak of a stochastic process, these results were extended to derive the behavior of two peaks in this paper. A special case, stationary, zero-mean Gaussian process was given. By using the method proposed in the paper, a desired effect was achieved, which laid a good foundation for the fatigue damage and fatigue life research.