Column Testing to Determine Colloidal Silica Transport Mechanisms

Mitigation of liquefaction potential in granular soil can theoretically be achieved through permeation of colloidal silica. Ho wever, practical application of this technique requires an efficient and adequate delivery of the silica. The purpose of this research is to evaluate colloidal silica transport mech anisms. The work consisted of short (0.9 m) column tests to identify the va riables that infl uence stabilizer transport through soil formations. It was found that the primary var iable influencing transport is the viscosity of the stabilizer solution. The results show that colloidal silica stabilizer can be delivered to the soil c olumn in an adequate concentration to stabilize the soil. Unconfined compression tests on the treated specimens indicate that treatment with 5 weight percent colloidal silica provides adequate strength for mitigation of liquefaction risk.