Porosity Fluctuations in Desiccating Samples of Grout-Stabilized Soil

Contaminant migration from polluted sites that are excessively permeable to fluids can be minimized by ground stabilization through grouting with cementitious materials. Analyses of the long term drying process of 2.75 mm diameter samples of cement–bentonite grouted soils from Dover, Del. in an environmental chamber maintained at a temperature of 25°C and relative humidity of 30% indicate that for most samples, the water-filled porosity (0.02–0.033) varied in a quasi-sinusoidal pattern with respect to drying time. Measurements of ultrasonic wave transit time with a James V-Meter correlated in time, with moisture loss determinations by weight loss measurements, show that in the initial 0–65 day drying period, the escape of moisture and consequent increase in air-filled porosity is responsible for the decrease in ultrasonic pulse velocity. Thereafter, increases in pulse velocity values ranging from 50 to 260 m∕s observed for the reaction products at sustained drying at 25°C, provide enough activation energy...