PEMANFAATAN ABU SEKAM PADI SEBAGAI SUBSTITUSI PARSIAL SEMEN DALAM PRODUKSI MATERIAL BANGUNAN BERBASIS GREEN CONSTRUCTION

Abstract

This study aims to examine the utilization of rice husk waste in the form of rice husk ash (RHA) as a partial substitute for cement in the production of building materials based on green construction principles. A quantitative experimental approach was employed through laboratory testing with RHA substitution levels of 0%, 5%, 10%, 15%, and 20% by weight of cement. The parameters evaluated included workability (slump), compressive strength at 7 and 28 days, density, and water absorption. The results indicate that increasing RHA content reduces slump values, reflecting decreased workability. In terms of compressive strength, a decline was observed at 7 days; however, at 28 days, mixtures containing 5% and 10% RHA showed improved strength compared to the control, with the optimum value achieved at 10% RHA (32.8 MPa). Additionally, density decreased while water absorption increased with higher RHA content. Overall, a 10% RHA substitution provides the best balance between mechanical performance and material efficiency. These findings suggest that rice husk ash has strong potential as a sustainable alternative material in environmentally friendly construction practices