Investigation into the short-term behavior of silty sand stabilized with colloidal silica

Injection in soils using traditional materials such as cement grout has its inherent shortcomings and lacks the potential for further development in industrial applications. Accordingly, application of novel materials for injection in soils with considerable ne contents for stabilizing and even making the soils impermeable is suggested. Among different stabilizers that are injectable in soils with ne materials, colloidal silica seems very suitable due to its very low viscosity, nontoxicity in nature, and adjustability of setting time for slow injection in ne soils. In this research study, laboratory tests were performed to examine the effect of colloidal silica on the strength parameters and the short-term behavior of silty sand. For characterizing the soil stabilized by colloidal silica, the silty sand samples with different silt values, in both unstabilized and stabilized conditions, were prepared with different concentrations of the stabilizer. Forty-five uniaxial tests and 75 unconsolidated-undrained compressional triaxial tests were conducted. An increase in the undrained cohesion of all samples was observed. On the other hand, two different trends were observed in the alteration of the undrained internal friction angle of soils with low and high ne contents.