Clayey soil stabilization using alkali-activated cementitious materials

• Published in: Materiales de construcción (Madrid) 2020-01, Vol.70 (337), p.211-e211
• Main Authors: Rivera, J. F., Orobio, A., Mejía de Gutiérrez, R., Cristelo, N.
• Format: Article
• Language: English
• Subjects: Activated clay; alkali-activated cement; blast furnace slag; Blast furnace slags; By products; Carbon content; Cement; Clay soils; clayey soil; Compressive strength; Contraction; Drying; Energy consumption; Environmental impact; Flexural strength; Fly ash; Granulation; Independent variables; Laboratories; Moisture content; Particle size; Portland cements; Soil cement; Soil classification; Soil lime; Soil mixtures; Soil stabilization; Variables; Wetting
• ISSN: 0465-2746; 1988-3226
• DOI: 10.3989/mc.2020.07519

In this study, a clayey soil classified as A-7-5 according ASTM D3282, was stabilized using alkali-activated cementitious materials (AAC) added to the soil dry in percentages of 20 and 30%. Fly ash (F1, F2) with high unburned carbon content (up to 38.76%), hydrated lime (L) and granulated blast furnace slag were used. Unconfined compressive strength and flexural strength at 28 days of curing and the durability after 12 wetting-drying cycles were evaluated. The results were compared with a soil-cement reference mixture. The soil treated with AAC-F1L showed a volume expansion of 0.51% and volume contraction of -0.57% compared with the 0.59% expansion and -0.68% contraction of the soil-cement reference mixture. Additionally, the mass loss after the wetting and drying cycles is only 3.74% which is slightly lower than the mass loss of the soil stabilized with ordinary Portland cement (OPC) (3.86%) and well below the value specified in Colombian regulations (7%).