强耦合结构动载荷识别方法

Dynamic Load Identification Method of Strongly Coupled Structures

以高速列车转向架构架为研究对象对强耦合结构的动载荷识别方法进行了研究。分析构架的结构特点及载荷系分布,以齿轮箱载荷识别为例通过加载齿轮箱载荷工况及干扰载荷工况获得强耦合边界测点的应变响应,通过三次样条空间插值的方法分别获得了三种工况下的强耦合区域内部的应变分布,将两种干扰载荷工况应变等高线交叉为零的点选为齿轮箱载荷识别测点,通过逐级加载的"载荷-应变"传递系数标定试验获得了标定散点,通过对散点进行回归分析获得最终的齿轮箱载荷系"载荷-应变"传递系数从而完成了载荷识别。通过线路实测获得了齿轮箱载荷系的时域数据,利用短时傅里叶变换得到了齿轮箱载荷系的时频图及频谱图,通过频域分析验证了该载荷解耦方法的有效性。

The dynamic load identification method of the strong coupling structure is studied with the bogie frame of high speed train as the research object.The structural characteristics of the frame and the distribution of the load system are analyzed.The strain response of the strongly coupled boundary measuring point is obtained by loading the gearbox load condition and the disturbing load condition,taking the gearbox load identification as an example.Through cubic spline space interpolation method,the strain distribution in the strongly coupled region under three working conditions is obtained,and the zero cross point of the strain contour of the two interference load conditions is selected as the load identification measuring point of the gear box.The calibrated divergence point is obtained by the calibration test of the load-strain transfer coefficient,and the final load-strain coefficient of the gear box is obtained by regression analysis.The time-domain data of the gearbox load system are obtained by measuring the actual railway line.The time-frequency diagram and frequency spectrum of the gearbox load system are obtained by using short-time Fourier transform.The effectiveness of the load decoupling method is verified by frequency domain analysis.