MONITORING SOIL SUCTION IN AN INDOOR TEST TRACK FACILITY

Tests on a full-scale pavement were conducted in an indoor controlled environment, the pavement track testing facility operated by the Saskatchewan Department of Highways and Transportation. The tests were conducted to evaluate the performance and reliability in using thermal conductivity sensors to measure matric suction in the subgrade under field conditions. Thermal conductivity sensors were installed at various locations and depths to monitor the matric solutions under the pavement structure. The thermal conductivity sensors were found to produce reliable and stable readings of the in situ matric suction over a long period of time. The effects of repetitive wheel loadings as well as ponding of the side slopes were investigated.