Geopolymers (GPs) have received much attention as an eco-friendly and sustainable alternative to conventional chemical additives, since they can be processed at room temperatures from aqueous solutions by utilizing waste materials (e.g. fly ash) or abundant natural sources (e.g. clay). A collaborative research study is carried out by teams from Texas A&M University (TAMU) and University of Texas at Arlington (UTA) to investigate the effectiveness of GPs for stabilizing base and subgrade materials by considering the strength and shrink-swell characteristics. Two types of clay, obtained from the North Dallas area, were mixed with a potassium-based GP synthesized from metakaolin and silica fume, at a ratio of 8 wt% of dry geopolymer to dry soil, and cured for a period of 7 days. Moisture-density relationship tests conducted show that treated soils have a higher optimum moisture content and lower maximum dry density as compared to untreated soils. Treated soils exhibited significant reduction in shrinkage and swell properties as compared to untreated soils. Additionally, unconfined compression strength tests also show an increase in strength of treated soils.
Radovic, M., & Puppala, A. (2018). Development of Environmentally-Friendly Stabilization Methods for Transportation Infrastructure Based on Geopolymers. Retrieved from https://digitalcommons.lsu.edu/transet_pubs/12