Use of Sugarcane Bagasse Ash as Partial Cement Replacement in Interlocking Stabilized Soil Blocks (ISSBs)

Global infrastructure needs for adequate housing, water provision and improved sanitation are on the rise. UN-Water estimates that 1 in 3 people still lack access to safe drinking water and about 4.2 billion people across the globe lack access to safely managed sanitation services. 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 and cost of cement-heavy construction, alternate construction techniques like appropriate earth technologies need to be adopted. Interlocking stabilized soil blocks (ISSBs), a type of compressed earth block (CEB), is one such technology that has recently gained recognition in East Africa. ISSBs are compressed instead of burned to gain strength and thus do not require the use of firewood for production. Moreover, ISSBs use less mortar than burned clay bricks, enable faster construction because of their interlocking mechanism and can be made on site saving transportation costs. The widespread adoption of ISSBs has been slow, however, due to higher unit costs (compared to burned clay bricks), lack of standardization and negative social attitude of people towards earth construction. To further reduce the cost and environmental impact of appropriate earth technologies, natural pozzolans (e.g., sugarcane bagasse ash) have been studied for their potential to partially replace cement as a soil stabilizer. This research presents an extensive literature review of the current construction methods used in Uganda and their drawbacks, the comparison of traditional construction methods with interlocking stabilized soil blocks (ISSBs) and the use of sugarcane bagasse ash as a primary and auxiliary stabilizer in interlocking soil stabilized blocks (ISSBs) and related products. Based on the findings of the literature review, this study proposes the optimum content for sugarcane bagasse ash in interlocking stabilized soil blocks. Additionally, this study contributes a best-practices research design flowchart and an experimental design for assessing the use of sugarcane bagasse ash as partial cement replacement in interlocking stabilized soil blocks