Correlation of the Na₂SiO₃ to NaOH Ratios and Solid to Liquid Ratios to the Kedah’s Soil Strength

¹ Center of Excellence Geopolymer and Green Technology (CEGeoGTech), School of Material Engineering, University Malaysia Perlis (UniMAP), P.O Box 77, d/a Pejabat Pos Besar, 01000, Kangar, Perlis, Malaysia
² Faculty of Engineering Technology, Universiti Malaysia Perlis (UniMAP), P.O. Box 77, D/A Pejabat Pos Besar, 01000 Kangar, Perlis, Malaysia
³ Schools of Civil Engineering, USM, Engineering Campus, 14300 Nibong Tebal, Seberang Perai Selatan, Pulau Pinang, Malaysia

^* Corresponding author: hazamaahnur@yahoo.com

Abstract

Geopolymer was used for the soil stabilization of Kedah’s soil at different ratios of solid to liquid and Na₂SiO₃ to NaOH in order to achieve the desired compressive strength. The geopolymerization process which produces an aluminosilicate gel was occurred due to the mixing of Kedah’s soil and fly ash with Na₂SiO₃ and NaOH. Soil stabilization by geopolymer was synthesized by the activation of fly ash and Kedah’s soil with Na₂SiO₃ and NaOH at different ratios of solid to liquid (1.5, 2.0, 2.5 and 3.0) and Na₂SiO₃ to NaOH (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0) at a specific constant concentration of NaOH solution of 6M. The compressive strength up to 5.12 MPa was obtained at 3.0 of solid to liquid ratio and 2.5 of Na₂SiO₃ to NaOH ratio in 7 days curing at room temperature.