结构振动疲劳加速试验技术研究

摘要

目的：提出一种用于评估随机振动环境下工程结构长期耐久性和疲劳可靠性的加速试验技术。方法通过开展一系列高斯和非高斯振动疲劳对比试验，系统研究影响结构振动疲劳寿命的各种因素，包括随机振动激励的均方根值、功率谱密度、带宽和峭度值等。结果非高斯随机振动激励的带宽和峭度值对结构振动疲劳寿命也有明显影响。结论当结构振动激励呈现明显的非高斯特征时，设计随机振动疲劳加速试验方案必须综合考虑振动激励的带宽和峭度值。%Objective To develop a new technology of accelerated vibration fatigue test to assess the long-term durability and fatigue reliability of engineering structures under random vibration environment.Methods Various factors that affect the struc-tural vibration fatigue life were systematically studied by Gaussianon-Gaussian random vibration fatigue tests, including root mean squares, power spectral density, power spectral bandwidth and kurtosis of acceleration excitation.Results The test results showed that the kurtosis value and the bandwidth of non-Gaussian random vibration excitation also had a significant impact on the structural vibration fatigue life.Conclusion If the structural vibration excitation shows obvious non-Gaussianity, the kurtosis value and the bandwidth must be considered for the quantitative design of random vibration fatigue accelerated testing.