【作者】 朱学旺；

【Author】 ZHU Xue-wang (Institute of Systems Engineering,CAEP,Mianyang,Sichuan,621900,China)

【机构】 中国工程物理研究院总体工程研究所；

【摘要】 振动试验的控制精度是影响试验有效性的关键因素之一,即使控制效果满足了试验的容差要求,但是在评价一项具体试验的动力学模拟效应时,实际控制结果在要求的参考谱附近的上下波动也需要谨慎地分析,因为试验规范规定的控制容差相对较宽(如随机振动控制容差多为±3dB)。本文研究响应控制方式下振动加速度控制的波动对结构振动疲劳损伤的影响。首先通过振动试验响应控制的动力学模型,应用振动分析的模态叠加方法,建立了加速度响应波动与应力响应波动之间的关系;然后,采用疲劳损伤线性模型,分析加速度控制的波动对结构振动疲劳损伤的影响。数值模拟中,针对常见试验规范给出的随机振动控制谱±3dB容差,讨论了结构动力学效应的变化趋势。更多还原

【Abstract】 Being one of key factors to affect validity of ground vibration test (GVT),the controlling tolerance must be applied warily in evaluting the GVT’s dynamic equivalence even if the tolerance has been satisfied with the requirement of GVT because the ordered tolerance contains generally too wide range in the standards (±3dB for random vibration,for example).Influences of the controlled acceleration’s tolerance on fatigue damage of structure in GVT are investigated in this paper.Based on the model of control for GVT,a relation of fluctuations between response acceleration and stress is presented.According to Miner’s linear accumulation fatigue damage rule,the effect of controlled acceleration’s fluctuation on fatigue damage is analysised.A simulation is provided for discussing the trend of dynamic equivalence of a structure in GVT under the condition of±3dB controlling tolerance.更多还原