Dynamic stress is one of the key indicators reflecting the fatigue characteristics of metro bogie frames. Considering the test costs, operation safety, and other factors, it is impossible to record all the dynamic stress data for the whole service period in the tracking test. Therefore, the overall stress spectrum is statistically deduced based on limited dynamic stress data samples, which can not only provide a basis for the fatigue reliability research of the bogie frame, but also save costs. In this paper, the typical fatigue control points in different areas of the frame with large equivalent stress are selected for research. The daily measured stress spectrum samples are obtained through the rainflow counting method, and the statistical stress spectrum is then compiled. Weibull distribution fitting of the stress spectrum is carried out to obtain the scale and shape parameter samples for different fatigue control parts. After sampling of the obtained parameter samples and conducting variance homogeneity tests as well as t-tests, the minimum sample size representing the overall distribution of the interval is obtained. Therefore, the shortest tracking test period reflecting the overall stress distribution of typical fatigue control parts can be obtained.

动应力是反映地铁转向架构架疲劳特性的关键指标之一。考虑到试验成本、运行安全等因素，跟踪试验不可能记录整个使用周期的所有动态应力数据。因此，基于有限的动应力数据样本统计推导整体应力谱，不仅可以为转向架构架的疲劳可靠性研究提供依据，而且可以节省成本。本文选取等效应力较大的车架不同区域的典型疲劳控制点进行研究。通过雨流计数法获取每日测量的应力谱样本，并编制统计应力谱。对应力谱进行威布尔分布拟合，得到不同疲劳控制零件的尺度和形状参数样本。对得到的参数样本进行采样，进行方差齐性检验以及t检验，得到代表区间总体分布的最小样本量。因此，可以获得反映典型疲劳控制零件整体应力分布的最短跟踪试验周期。