Ground penetrating radar for moisture assessment in railway tracks: An experimental investigation

Abstract

The assessment of the condition of railway substructure is particularly linked to the tracking of degradation mechanisms that are tied to the phenomenon of water infiltration, causing moisture accumulation in the underlying layers. Such deterioration incurs substantial costs, while reducing the useful life of the track infrastructure. In tracking such processes, a promising solution is found in the use of Ground Penetrating Radar (GPR) technology, which employs non-invasive radar pulses to map the subsurface, and possibly detect water infiltration. Despite previous efforts in this direction, the technology remains relatively under-explored and lacks comprehensive studies to establish its suitability for this task. In this work, we present a detailed experimental analysis carried out on a controlled railway track section, which was built by the Swiss Federal Railways for this campaign. Our findings demonstrate that GPR systems can effectively detect moisture infiltration in railway tracks, although several challenges are to be addressed for the development of accurate, automated procedures. The experimental data is compared against numerical simulations of the physical configurations of the test railway track, which were conducted via the gprMax software.