Viscosity-Enhanced EICP Treatment of Soil

Glycerol and xanthan gum were employed to enhance the viscosity of the cementation solution in soil treated with enzyme-induced carbonate precipitation (EICP). The effect of increasing the viscosity of the solution was investigated because it may facilitate EICP treatment by retaining cementation solution as precipitation occurs. Columns 51 mm in diameter and 102 mm in height of Ottawa 20/30 and F-85 sands were treated with EICP solution containing no thickener, 50% (v/v) glycerol, and 0.25% (w/v) xanthan gum. Some columns had open bottom to allow drainage and some were capped to retain the cementation solution. Xanthan-enhanced EICP solution showed the highest level of fluid retention. Results showed that EICP-Treated sand can be cemented with the addition of a viscosity enhancer but that cementation quality may be affected. The level of retention did not have a strong relationship with uniformity of cementation and did not result in enhanced unconfined compressive strength.