COMPARISON EFFECTS OF SAW DUST ASH AND RICE HUSK ASH ON THE COMPRESSIVE STRENGTH OF CONCRETE

This study investigates the comparative effects of sawdust ash (SDA) and rice husk ash (RHA) on the compressive strength of concrete. The research evaluates the potential of these agricultural by- products as partial cement replacements in concrete. Concrete samples were prepared with 0%, 5%, 10%, and 15% ash replacement levels for both SDA and RHA, 0.5 water cement ratio and 1:2:4 mixing ratio was used. Compressive strength tests were conducted using Universal Testing Machine (OKH_ 1000_WE (Serial Number 2101E01) on the cubes of size of 150mm x 150mm by 150mm x 150mm. at 7, 14, and 28 days to assess their impact over time. Results revealed that a 5% replacement level of both SDA and RHA yielded higher compressive strengths than the control mix.. The 10% replacement level for RHA demonstrated the highest long-term strength, achieving 18.15 MPa at 28 days, making it a promising option for applications requiring sustained strength. However, at a 15% replacement level, both materials exhibited a reduction in strength below the control, suggesting that excess ash disrupts the hydration process and matrix integrity. These findings highlight the potential of SDA and RHA as eco-friendly cement alternatives, with RHA showing particularly favorable results for long-term strength