DEPTH OF BALLAST, BALLAST FOULING LEVELS, FORMATION FAILURE AND SUBGRADE EROSION
Changes can occur at different stages in the lifetime of a ballasted trackbed under repeated loading. These include the generation of fines which may clog ballast void space, the failure of the formation leading to ingress of fines through pumping and localised settlement of the formation leading to the growth of ballast pockets.
Traditional trackbed inspection strategies such as visual patrols and track geometry measurements are generally late indicators of subgrade and ballast quality related issues.
Monitoring ballasted trackbed with Zetica’s Advanced Rail Radar (ZARR) allows decisions to be made on timely and cost effective maintenance interventions. Combining track geometry measurements with GPR provides unique information to plan a holistic ballast and trackbed management strategy.
Regular monitoring with GPR also allows decisions to be made on timely and cost effective interventions to remediate structures. For example, early indications of ballast thickening derived from inspection train based GPR systems can be flagged for detailed follow-up with ground GPR surveys.