疲劳损伤等效在随机振动试验中的应用

以疲劳损伤等价为基础的随机振动试验是评价结构振动环境适应性能力的重要手段.将基于位移模态和应变模态的模态叠加方法分别应用于结构振动位移响应和应力响应的分析中,建立了随机振动试验不同激励条件下,结构振动响应的关系;将结构随机振动应力响应的峰值概率分布通用关系应用于疲劳损伤评估,导出了振动疲劳损伤等效关系.以一个试验为例介绍了疲劳损伤等效原则在随机振动试验中的应用.

Application of Fatigue Damage Equivalence in Random Vibration Test

Random vibration test technique based on equivalence of fatigue damage is an important method in evaluation of vibra- tion environmental worthiness of the structure.The mode superposition methods about displacement mode and strain mode were applied to analyze structure responses of displacement and stress.A relation to the structure vibration responses was found corresponding to dif- ferent vibration excitations in test.The general formula of peak probability distribution of stress response was applied to estimate the fa- tigue damage and an equivalent relation to fatigue damage was developed.A procedure for test design and results evaluation was intro- duced to the application of the equivalent fatigue damage relation on random vibration test.