Development of Bricks Using Waste Materials

Abstract

The fastest developing country in the world, such as India, currently has a rapidly growing demand for infrastructure projects. In response, the government has initiated housing project schemes that have employed a large number of migrants, including both men and women. To meet this demand, there are over 150,000 brick units that provide direct employment to more than 8 million workers. The conventional brick system uses sand and soil to hand-mold bricks, which are fired at temperatures of 800-1100°C. This process pollutes the environment and leads to the loss of topsoil. The project’s objective is to produce unfired bricks using 100% waste materials like fly ash, stone dust, mill scale, hydrated lime, and gypsum. This will help reduce the reliance on coal and diesel, preserve topsoil, minimize harmful emissions, and manage industrial waste. The study will focus on determining the physical and chemical properties of the raw materials. The goal is to develop the mix proportions for casting various brick mixes and then to assess the properties of the bricks, such as compressive strength, water absorption, tolerance, and efflorescence through an experimental program. The base mix consists of ’fly ash-stone dust-hydrated lime-gypsum’, with the stone dust being replaced by mill scale at 10%, 20%, 30%, and 40% in series-A to examine their effects on the brick properties. The results showed that 40% replacement led to a reduction in strength compared to the base mix, but water absorption showed better results. On the other hand, 20% replacement demonstrated better compressive strength at 7 and 14 days as compared to the base mix. In series-B, the mill scale was replaced by stone dust at 5%, 10%, 15% and 20%. From that, the 15% replacement has shown the maximum compressive strength of 13.5 MPa at 28 days as compared to other mix proportions. Along with that, the 20% replacement has shown the least water absorption of 15.73% as compared to the base mix of 21.04%.