Inversion Method of Ballastless Track Performance Degradation Based on Multi-channel Analysis of Surface Waves

Abstract:

The inversion method of ballastless track performance degradation based on the multi-channel analysis of surface waves was proposed. Based on the theoretical surface wave dispersion curve， the dispersion characteristics of ballastless tracks with varying degrees of degradation were analyzed. A method for inverting the ballastless track performance degradation was constructed， and the effect of excitation frequency and detector placement mode on the inversion effect was studied. The results indicate that the shear wave velocity of CA mortar and track slabs respectively determines the surface wave dispersion curve of ballastless tracks at low and high frequencies. To enhance the inversion effect， the excitation frequency is recommended to be set at 50 kHz， the minimum offset distance should be greater than or equal to 0.05 m， and the channel spacing between tracks should be 0.05 m. Moreover， the length of the detector arrangement should be increased as much as possible.