一种修正的基于临界平面多轴循环计数法

进行多轴随机载荷下的结构疲劳寿命分析时,需选择合适的循环计数方法提取损伤事件.结合疲劳寿命预测方法中的临界平面法,对Langlais多轴循环计数法进行了讨论,并在此基础上完成了对Langlais多轴循环计数法的修正.修正后的多轴循环计数法可以精确地考虑到1个主通道循环内辅助通道的全部载荷信息;同时发展了修正Langlais法新的实现方法,可以用于封闭曲面法计算有效载荷;对三点雨流计数法的循环计数起始点选择进行了改进,提高了循环计数效率.

A Modified Multiaxial Cycle Counting Based on Critical Plane Methods

Abstract： A proper cycle counting method should be selected when predicting the fatigue life of engineering components under variable amplitude and multiaxial random loading. Based on the critical plane method, the Langlais multiaxial rainflow counting algorithm was discussed. Then, a modified Langlais multiaxial rainflow algorithm was proposed and a realization method for modified Langlais multiaxial rainflow algorithm was developed. The modified Langlais multiaxial rainflow algorithm can accurately take into account all load information in the auxiliary channel, corresponding to a complete cycle in the counting channel. And it can be used for the enclosing surface method to calculate the effective stress or strain range. For a new cycle counting process of the 3 point rainflow method, the method of choosing the starting point was modified, which improved the efficiency of cycle counting.