Experimental study of subgrade soil stabilised with geopolymer based on glass powder and calcium carbide

Considering cement environmental sustainability issues, geopolymer materials composed of glass powder and calcium carbide could be a suitable alternative to the cement. In order to improve the mechanical properties of the subgrade soil, an experimental study, on three series of natural soil, Cement-Stabilized Subgrade (CSS), and Geopolymer-Stabilized Subgrade (GSS) soils have been presented. All soil specimens made up with various silt ratios, and studied under UCS test. Various mix design of geopolymer materials were prepared for UCS test and the optimal ratio of mix design, in which the resulting geopolymer contains the highest soil compressive strength. The results indicates that soil mechanical properties are a function of additives and fines contents. GSS soil could be used as an effective stabilizer compared to CSS one. Furthermore, SEM analysis proved that GSS soil tends to have a uniform and dense microstructure, and the geopolymerization reaction between the soil particles, was appropriate.