高速动车组转向架端部悬挂件对构架应力的影响

为了探究高速动车组转向架端部悬挂件对构架应力的影响规律，依据UIC 615-4标准，对转向架构架与端部悬挂件进行了有限元仿真，校核了构架疲劳强度；开展了实际运营条件下的跟踪测试试验，分析了不同位置测点应力的时、频域特征，计算了等效损伤；结合模态计算探讨了转向架端部悬挂件对构架侧梁端部应力状态产生较大影响的成因。分析结果表明：依据标准计算的弹簧帽筒区域的疲劳强度满足要求；远离辅助安装座区域的弹簧帽筒测点，实测最大等效损伤为0.01，靠近辅助安装座区域的弹簧帽筒测点，实测最大等效损伤为0.45，明显高于远离辅助安装座区域的测点；对于靠近辅助安装座区域的弹簧帽筒测点中，弹簧帽筒外侧测点即更靠近辅助安装座区域测点的等效损伤均高于内侧测点，二者等效损伤最大相差84.16%；实测数据存在38 Hz的主频，与辅助安装座和构架连接整体的第4阶模态接近，结合实测数据时频分析结果证明，车辆行驶与轨道不平顺波长共同作用产生的激扰，激起了辅助安装座和构架连接整体的第4阶模态，发生P₂共振导致弹簧帽筒区域产生过大应力。

Effects of suspension parts at end of high-speed EMUs bogies on frame stress

To explore the effects of suspension parts at the end of high-speed EMUs bogies on frame stress, the finite element simulations of bogie frames and end suspension parts were performed in accordance with the UIC 615-4 standard, and the fatigue strength of the frame was investigated. A tracking test was performed under actual operating conditions. The time- and frequency-domain characteristics of the stress at the measuring points at different locations were analyzed, and the equivalent damage was calculated. Through modal calculation, the causes of the significant influences of bogie-end suspension parts on the stress state of the frame side beam end were identified. Analysis results show that the fatigue strength of the spring cap area, which is calculated according to the standard, meets the requirements. The maximum measured equivalent damage at the measuring points of the spring cap far from the auxiliary mounting seat area is 0.01. The maximum measured equivalent damage at the measuring points of the spring cap close to the auxiliary mounting seat area is 0.45, which is significantly higher than that at the measuring points far from the auxiliary mounting seat area. For measuring points of the spring cap close to the auxiliary mounting seat area, the equivalent damage at the measuring points on the outer side of the spring cap, such as those closer to the auxiliary mounting seat area, is higher than that on the inner side, and the maximum difference between the two equivalent damage values is 84.16%. The measured data have a dominant frequency of 38 Hz, which is close to the fourth-order mode of the combination of the auxiliary mounting seat and bogie frame. Combining these observations with the time-frequency analysis of the measured data, it can be deduced that the excitation generated by the combined action of vehicle driving and track irregularity-related wavelengths excites the fourth-order mode of the combination of the auxiliary mounting seat and bogie frame, moreover P₂ resonance occurs, resulting in excessive stress in the spring cap area. 2 tabs, 22 figs, 30 refs.