Application of TDR Test Probe for Determination of Moisture Changes of Railway Substructure Materials

Abstract

The initial part of the paper characterizes a non-destructive TDR (time domain reflectometry) method for measuring moisture. This method is used to identify the moisture changes in the materials incorporated in the structural layers of the railway models built at a 1:1 scale (experimental stand DRETM). The subsequent part specifies the procedure for calibrating the TDR probe for selected building materials composing the measuring profiles of the experimental stand (Liapor fr. 1/8 mm, sand and crushed aggregate fr. 0/31.5 mm). The result of the TDR probe calibration is the calibration curves for the tested building materials, which can be used to identify the real moisture values in the railway line structure, in any season. The specified moisture values represent the necessary inputs for the numerical modeling of the non-traffic load (climatic factors) on the railway line using the SoilVision software.