Application of Spatial Time Domain Reflectometry for investigating moisture content dynamics in unsaturated sand

The strength of unsaturated soil is defined by the soil water retention behavior and such suction acting inside the soil matrix. In order to obtain suction and moisture profile in the vadose zone specific measuring techniques are needed. Time Domain Reflectometry (TDR) conventionally measures moisture at individual points only. Therefore, Spatial Time Domain Reflectometry (Spatial TDR) was developed for characterizing the moisture content profile along the unsaturated soil strata. This paper introduces an experimental set-up used for measuring dynamic moisture profile in high spatial and temporal resolution. Preliminary measuring results are presented and discussed.