基于试验与仿真相结合的动应力混合模拟

A new dynamic stress hybrid calculation method based on experimentation and numerical simulation

将已测试位置动应力试验数据用于结构上不可测试位置的动应力时间历程模拟,提出一种试验与仿真相结合的动应力混合模拟新方法。该方法也可用于载荷谱无法准确获取结构或新修改结构的动应力时间历程数据模拟,克服了传统动应力仿真算法要求对结构真实服役环境下载荷时间历程准确获取的限制条件,解决了试验无法直接测量位置动应力时间历程获取的问题,给出了一种基于原服役结构测试数据预测新修改结构疲劳寿命的方法。基于应变模态理论推导了具体实现公式,实例验证了该方法的有效性。研制了相应的动应力混合模拟软件,结合线路动应力试验数据,进行机车车辆转向架未测试位置的疲劳寿命预测和评估。

This paper presents a dynamic stress hybrid calculation method based on experimentation and numerical simulation.On some specific positions,the dynamic stress-time history which can't be measured with strain gauge can be obtained by the method.The method can also be used for calculating dynamic stress-time history of structure whose load-time history can't be measured directly,and by it the dynamic stress-time history of the modified structure can be predicted by the dynamic stress-time history which was measured on unmodified structure.Based on strain mode theory,the calculation formulas were deduced in detail in the paper.On the basis of these formulas,a software system was developed for vehicle bogie fatigue life estimation.The numerical simulation and the experiment show that the dynamic stresstime history can be obtained by the proposed method easily and accurately.