Abstract
Engineered water repellency (EWR) is a soil improvement method that involves intentionally modifying natural soil to become hydrophobic. Potential applications of EWR include landfill covers, frost mitigation, and moisture control in pavement systems. Designing with EWR requires knowledge of water entry pressure (WEP) and its relationship to pore size and contact angle for a given soil. In this study, a commercial grade organosilane (OS) was examined using a new methodology to establish the WEP. Soil specimens were placed in a triaxial-type cell and tested with a step-wise pressure profile from 0.7 to 117 kPa. The results indicate that for a given dosage, a relatively higher density yields the least water infiltration and a larger WEP. The maximum dry density (e.g., 95% of standard proctor effort) should be specified for field application.