通过线路测试获取CR400BF 400 km/h运行条件下主要车下设备激励的振动特性，考虑不同设备安装形式对振动特性的影响，采用统计容差法、包络法、疲劳损伤谱等方法归纳不同方向车下设备随机振动实测谱和规范谱，并与GB/T 21563—2018进行对比及标准适用性分析。结果表明：400 km/h条件下弹性安装设备振动RMS均低于标准值，刚性安装设备横向RMS为0.391 9 m/s²,超出标准值0.37 m/s²;车下设备均存在由轨道P2力引起的40～50 Hz激励主频，与标准5～20 Hz振动主频存在明显差异；标准谱作为考察400 km/h弹性安装结构的载荷谱相对保守，对400 km/h刚性安装设备的适用性较差。基于Dirlik应力分布模型，推导出双斜率S-N曲线下激励放大倍数同疲劳寿命比例呈现双对数变化关系，以动车组污物箱为例，获取不同疲劳标准下加速试验时间同加速比之间的关系，为随机振动台架试验提供参考。

The vibration characteristics of CR400BF equipment excitation under 400 km/h are obtained through line test. Considering the influence of installation forms, the statistical tolerance method, envelope method, fatigue damage spectrum and other methods are adopted to summarize the vibration spectrum of under-vehicle equipment in different directions, comparation with GB/T 21563 is conducted, and the applicability of the standard is analyzed. The results show that the vibration RMS of the elastic mounted equipment under 400 km/h is lower than the standard value, and the transverse RMS of the rigid mounted equipment is 0.391 9 m/s², which is more than the standard value of 0.37 m/s². All equipments have the excitation main frequency of 40-50 Hz caused by the P2 force, which is significantly different from the standard vibration main frequency of 5-20 Hz. The standard spectrum is relatively conservative as the load spectrum of the 400 km/h elastic mounting structure, which is less applicable to the 400 km/h rigid mounting equipment. Based on the Dirlik distribution model, a double logarithmic relationship between the excitation amplification and the fatigue life under the double-slope S-N curve is deduced. Taking the EMU sewage bins as an example, the relationship between the acceleration test time and acceleration ratio under different fatigue standards is obtained, which is a reference for the random vibration bench test.