A TYPICAL REVIEW ON GEOPOLYMERIZATION AND INFLUENTIAL FACTORS AFFECTING MECHANICAL PROPERTIES OF LATERITE SOILS STABILIZED WITH GEOPOLYMER

Abstract

In Vietnam, in recent years, research and application activities of geopolymer to improve the physical and mechanical properties of soil have increased, including weathered soils (laterite soils). However, critical studies on the polymerization process as well as the primary factors affecting the physico-mechanical properties of laterite soil are relatively limited. This paper presents a critical review on the polymerization mechanism, the influential factors affecting the mechanical properties of geopolymer materials. Specifically, the type or origin of AluminoSilicate materials and the alkaline environment play a vital role in the polymerization process. For the improvement of the physical and mechanical properties of soils with high clay/silt content and plasticity, beside using the appropriate sodium hydroxide (NaOH) concentration, other factors need to be considered, such as AluminoSilicate material content, Si/Al ratio. Besides, the strength of materials using geopolymer generally reaches the optimal value as the ratio Si/Al = (1.85¸2.0); yet, there are still studies showing that the strength increases even when the ratio Si/Al ³ 2.0; therefore, more studies need to be conducted to evaluate the influence of Si/Al ratio more clearly.