福斯罗W300扣件系统组装状态下刚度特性试验研究

利用高频疲劳动刚度试验平台，结合高速铁路实际运行状况，对福斯罗W300扣件系统组装状态下刚度特性进行研究，得到以下结果. 1)不同预压荷载下，静态和动态刚度有相同增长趋势，20 kN(40 kN)预压荷载下静刚度值比无预压荷载下增大17.7%(59.5%),40 kN下静刚度值明显超出扣件系统静刚度设计限值. 20 kN(40 kN)预压荷载下动态刚度比0 kN下增大4 dB(10 dB). 2)扣件系统静态和动态刚度均表现出低温敏感性，当温度低于20℃时，静刚度值随温度降低而上升，特别是在-30℃到-60℃时静刚度值急剧上升，-50℃(-60℃)时静刚度是20℃时的1.4(4.4)倍.-30℃下，其动态刚度比30℃时增大8～10 dB，弹性单元体丧失弹性，直接影响扣件系统减振效果. 3)扣件系统刚度在5～1 000 Hz时有明显频变特性，预载一定时，动态刚度随频率增大而增大，1 000 Hz下动态刚度值比国家标准5 Hz下增大15 dB.

Experimental study on stiffness characteristics of Vossloh W300 fastener system under assembly state

Using the high-frequency fatigue dynamic stiffness test platform and combining with the actual operation conditions of high-speed railway, the stiffness characteristics of Vossloh W300 fastener system under assembly state were studied, and following results were obtained. 1) Under different preloading loads, the static and dynamic stiffness have the same growth trend, and the static stiffness under 20 kN (40 kN) preloading load is 17.7% (59.5%) higher than that without preloading load, the static stiffness corresponding to 40 kN obviously exceeds the design limit of the overall static stiffness of the fastener system. The dynamic stiffness under 20 KN (40 kN) preloading load is 4 dB (10 dB) greater than that under 0 kN. 2) Both the static and dynamic stiffness of the fastener system show low temperature sensitivity. When the temperature is lower than 20 ℃, the static stiffness increases with the decrease of temperature, especially the static stiffness increases sharply from ?30 ℃ to ?60 ℃, and the static stiffness at ?50 ℃ (?60 ℃) is 1.4 (4.4) times that of 20 ℃. The dynamic stiffness at ?30 ℃ is 8~10 dB greater than that at 30 ℃, and the elastic unit loses elasticity, which directly affects the vibration reduction effect of the fastener system. 3) The fastener system stiffness has obvious frequency variation characteristics within 5~1000 Hz. When the preload is certain, the dynamic stiffness increases with the increase of frequency, and the dynamic stiffness value at 1000 Hz is 15 dB higher than that at 5 Hz in the national standard.