Improving the Mechanical Properties of Soil and Foundations Through Synthesis of Diatomite, Mica, and Fly Ash-Based Geopolymer

This study aimed to improve the mechanical properties of soil and foundations through geopolymer synthesis. The soil used in this research was wind-blown sand exposed to erosion. To examine the mechanical properties of the soil, laboratory tests were conducted, including Atterberg limits, soil permeability coefficient, sand equivalent value, soil pH, optimum moisture content, unconfined compressive strength (UCS), and particle size distribution. The results indicated that the uniformity coefficient (Cu) and curvature coefficient (Cc) were 2.5 and 1.23, respectively, classifying the soil as poorly graded. Based on the soil’s silt and clay content, it was classified as sand. The particle size distribution test showed that 5% of the soil passed through the No. 200 sieve. Hence, the soil is coarse-grained and poorly graded. The soil density was determined to be 2.65 g/cm³, confirming that the soil is sandy and quartzitic, and due to its lack of cohesion, it exhibits zero compressive strength. The permeability coefficient was 1×10⁻³ cm/s, the sand equivalent value was 79%, and the soil pH was 7.7. The geopolymer sample with diatomite exhibited the highest strength.The key factor in the geopolymerization process is SiO₂, and with strength comparable to cement, it is a suitable alternative to reduce the environmental impact of cement production.