Assessment of the compressive strength and water absorption properties of cement stabilised clay bricks admixed with sugarcane bagasse ash from power cogeneration boilers

Abstract

Global infrastructure needs for adequate housing, water provision, and improved sanitation are on the rise. Rapid urbanization and the global refugee crisis have also increased the demand for adequate and efficient housing. UN Sustainable Development Goals cannot be achieved until these needs are met. Given the high environmental impact of carbon production and the cost of cementheavy construction, alternate construction materials like Natural pozzolans need to be adopted. The utilization of sugarcane bagasse ash has been one of the widely adopted pozzolans for partial replacement of cement in the construction industry. Previous studies have shown that sugarcane bagasse ash can be used as a cement replacement in construction materials like soil stabilization. This research aims to investigate the possible utilization of sugarcane bagasse ash from power cogeneration boilers as a partial stabilizer replacement in bricks. Soil-stabilized bricks were made of soil and stabilized with cement and sand added to reduce plasticity. The bricks were manufactured locally using a wooden mould of 215*115*100mm and cured over 28 days to allow strength gain. Sugarcane bagasse ash of 10%, 20%, and 30% as a percentage of cement for two control samples (0% bagasse ash) with cement at 5% and 10% stabilized were used in the manufacture of the brick samples. Representative samples were then obtained and laboratory tests were carried out to ascertain the properties of the bricks. The average compressive strength of the bricks ranged from 3.22 MPa to 3.83MPa for 10% cement stabilized and 2.36MPa to 3.67MPa for 5% cement stabilized for all the different mix ratios, which satisfied the minimum compressive strength for stabilized soil blocks, US 849: 2011. All the brick samples depicted water absorption values that were way lower than the recommended maximum of 15% by weight, with experimental values ranging from 7.00% to 8.44% and 5.7% to 8.77% for the 10% cement sample and 5% cement sample respectively. The optimum mix ratio chosen was 20% of the ash by weight of cement (10%) since samples of this mix had the maximum compressive strength of 3.83 MPa with an acceptable average water absorption capacity of 8.31% by weight.