随机振动结构Von Mises应力过程峰值概率密度函数的研究

随机振动载荷作用下结构的多轴疲劳分析非常复杂,利用Von Mises应力准则将多轴应力转换为单轴应力是一条简单而有效的途径。在频域利用Von Mises应力对结构进行多轴疲劳分析的前提是必须获得Von Mises应力过程中应力循环的概率密度函数。本文利用平稳随机过程的穿越分析和极值的概率分析,给出了计算Von Mises应力过程峰值概率密度函数的公式,为进一步进行疲劳损伤及寿命分析打下了基础。

Peak Probability Density Function of Von Mises Stress Process

For multiaxial fatigue damage analysis,it is a simple and efficient way to convert multiaxial stress into uniaxial one with Von Mises criterion.The precondition of structure multiaxial fatigue analysis in frequency domain with Von Mises stress is to obtain its peak probability density function.Based on the threshold crossing analysis and the peak distribution analysis of stationary random process,the general expression for the peak probability density function of a Von Mises stress process is described.