Doppler effect in high-speed rail seismic wavefield and its application

We demonstrate by theoretical analysis that periodically distributed viaduct piers of high-speed rail result in the Doppler effect in the seismic wavefield of high-speed rail at specific frequencies and analyze the Doppler effect’s influence on the wavefield’s spectrum feature. We further verify our theoretical prediction by using observational data of the high-speed rail seismic wavefield in Rongcheng, Hebei Province, China. We find that the wavefield component with a noticeable Doppler effect vibrates in the propagation direction and only has a unique apparent wave speed, indicating that P-wave is dominant. Furthermore, we propose a speed measurement method based on the Doppler effect and measure the wave speed of the medium along the rail. Measurement results are highly stable and consistent.