Spatial dynamic response laws of the ballastless track structure in high‐speed railways under vibration loads

Abstract The ballastless track in a high‐speed railway (HSR) is the primary structure that directly bears the load of high‐speed trains and its dynamic responses directly reflect the operation state of HSRs. However, there are few field test results about spatial dynamic responses of HSR ballastless tracks in previous research. Taking a prototype of an HSR ballastless track as the research object, dynamic response data of the HSR ballastless track were measured by arranging acceleration sensors thereon and applying vibration loads at different positions. The spatial dynamic response laws of the HSR ballastless track were explored in detail. The research results show that in the vertical, transverse, and longitudinal directions, the maximum accelerations all occur near the exciting points; the acceleration in the longitudinal direction is attenuated mainly in the supporting layer and has become very small after being transmitted to the top of the subgrade. The research findings provide guidance for the monitoring of dynamic responses of HSR ballastless tracks.