Effect of cement and sodium silicate stabilization on the unconfined compressive strength of organic soil

The study was aimed at determining how addition of  cement and sodium silicate to organic soil influenced itsunconfined compressive strength. Cement and sodium silicate were used as the additive stabilizing agents to treat organicsoil which is one of  the most problematic soils when it comes to geotechnical engineering. Organic soil samples uponwhich stabilization was conducted were obtained from Kayseri Free Area, Turkey. Index properties of  organic soil werefirst determined to help understand the nature of  the soil sample. Tests to determine the engineering properties of  the soilwere conducted before and after addition of  the stabilizing materials. Cement was used to replace soil in percentages of10% and 20% while sodium silicate was added in compositions of 3% and 6%. The stabilizing materials, cement and sodiumsilicate, were added in proportions of  percentages of the dry weight of  the organic soil. From the different compositions,four samples were obtained upon which the effect of  cement and sodium silicate on unconfined compressive strength ofthe organic soil was determined. Standard proctor test was used to help obtain the maximum dry density and the optimummoisture content of the untreated sample and the treated samples. Unconfined Compressive Strength (UCS) tests wereperformed to determine the extent to which the UCS of the soil increased as the stabilizing materials were added. UCS testswere conducted on air cured samples for 1, 7, and 28 days.From the UCS tests conducted, sodium silicate and cement wereseen to improve the strength of organic soil. The tests also depicted that longer curing periods improved strength even more.Higher values were obtained for 7 days cured samples than for 1 day samples with the highest values being obtained for 28days cured samples. Design mixes with higher cement and sodium silicate compositions gave the highest values of  strength.In conclusion, sodium silicate and cement give positive results when it comes to stabilizing organic soil.