Influence of temperature- and frequency-dependent properties of elastic layer on vibration response of vibration reducing CRTSⅢ slab ballastless track

The elastic layer was taken as the research object. Firstly, through its dynamic mechanical test and based on the high-order fractional derivative FVMP model combined with the temperature-frequency equivalent principle, the temperature- and frequency-dependent properties of elastic layer were characterized. Then the model was applied in the vertical vehicle-track coupled system. Finally, the effect of temperature- and frequency-dependent properties of the elastic layer on track structure vibration response was analyzed. The results show that temperature and loading frequency have significant effects on the dynamic mechanical properties of elastic layer. The high-order fractional derivative FVMP model can accurately characterize this property. In the time domain response, the peak values of vertical wheel-rail force, rail vertical displacement, rail vertical vibration acceleration and slab track vertical vibration acceleration of FVMP model are significantly greater than those of K-V model. In the middle and high frequency band, the response of each part of the track structure shows that the response of FVMP model are greater than that of K-V model, and the response of each part of track structure decreases with the decrease of temperature. Therefore, in order to improve the accuracy of track structure prediction, it is necessary to consider the temperature- and frequency-dependent properties of elastic layer. © 2021, Central South University Press. All right reserved.