Laboratory evaluation of geopolymerization reaction in bricks production

Recently, Energy and environmental factors play important roles in economy and politics of different countries due to increasing complexity and evolution of international community. Therefore introducing and designing new materials which reduce manufacturing cost, decreasing energy consumption and being environmental-friendly are crucial. This paper studies the feasibility of utilizing laterite soil for production of eco-friendly bricks based on the geopolymerization technology. The procedure for producing this kind of brick simply includes: mixing laterite soil with an alkaline solution, water, sand or without sand and forming the bricks by compressing the mixture in a mold under a specified pressure. Final step is curing the bricks at a slightly elevated temperature. Unlike the conventional method for producing bricks, the new procedure does not require high temperature kiln firing hence it has significant environmental benefits. In this study, effects of five major factors including types of alkaline solution, addition condensed silicafume to mixture, curing temperature, amount of laterite soil and age of bricks were investigated. The results for compressive strength, water absorption and ultrasonic test value were analyzed by statistical method. Findings show that laterite soil available in northwest of Iran can be used to produce eco- friendly bricks based on geopolymerization technology to meet the Iran standard and ASTM requirements for engineering bricks.