In 2002 the Ohio Department of Transportation (ODOT) initiated a researchproject to assess the effectiveness of the drainable base materials underin-service conditions. To that end, time-domain reflectometry (TDR) probes, Measurements Research Corporation (MRC) thermistor probes, Corps of Engineers Cold Regions Research and Engineering Laboratory (CRREL) resistivity probes, two weather stations, and piezometers were installed at I-90 project site to monitor moisture content, pavement temperature, frost depth, climatic data, and ground water elevations, respectively. The main focus of this paper is to investigate the moisture, temperature, and frost depth regimes under different permeable base materials over six years of data monitoring. Pavement sections built with cement treated and asphalt treated permeable base materials showed lower variations in their subbase and subgrade moisture contents than those built with unbound permeable base materials. Based on the field long-term moisture monitoring, it is not recommended to use either ODOT 304 or ODOT 307-IA as a drainable base materials in the subsurface drainage design. There was no evidence of full saturation in base and subbase materials. Pavement temperature follows a sinusoidal function with time; while the pavement temperature increases in the summer season, it decreases in the winter season. None of the instrumented sections shows any freezing action throughout the monitoring period.
Abstract