SUSTAINABLE CONCRETE DEVELOPMENT USING RICE HUSK ASH AS PARTIAL CEMENT REPLACEMENT

Abstract

The increasing demand for sustainable construction materials has driven the exploration of alternative cementitious resources to reduce the environmental impact associated with conventional concrete production. This study investigates the feasibility of using rice husk ash as a partial replacement for cement and evaluates its influence on the mechanical performance and overall behavior of concrete. Rice husk ash, an agricultural byproduct rich in amorphous silica, exhibits significant pozzolanic activity when processed under controlled conditions. Concrete mixes were prepared with varying replacement levels of rice husk ash, and their compressive, tensile, and flexural strengths were analyzed. The results indicate a consistent improvement in mechanical properties up to an optimal replacement level of 10%, beyond which a gradual decline is observed. The enhancement in strength is attributed to the formation of additional calcium silicate hydrate gel and the refinement of pore structure, leading to a denser and more durable matrix. The findings also reveal a strong correlation among mechanical properties, while the relationship between rice husk ash content and strength remains non-linear, emphasizing the importance of optimized proportioning. In addition to performance benefits, the incorporation of rice husk ash contributes to environmental sustainability by reducing cement consumption, lowering carbon emissions, and promoting the utilization of agricultural waste. The study confirms that controlled use of rice husk ash offers a viable approach to achieving both structural efficiency and sustainability in concrete production, with 10% replacement identified as the most effective proportion.