Experimental Investigation of Bamboo Leaf Ash Blended Concrete for Sustainable Construction

Abstract

This study investigated the feasibility of using bamboo leaf ash (BLA) as a partial replacement for ordinary Portland cement in the production of sustainable concrete. The pozzolanic potential of BLA was evaluated through chemical analysis, which showed that the combined content of SiO2 , Al2O3 , and Fe2O3 was 74.61%, satisfying the requirements of ASTM C618 for Class N pozzolans. Concrete mixtures were prepared with 0%, 5%, 10%, 15%, and 20% BLA replacement levels by weight of cement, targeting a characteristic compressive strength of 25 MPa. The effects of BLA incorporation on cement paste properties, workability, compressive strength, water absorption, and sulfate resistance were experimentally investigated. The results indicated that mixtures containing 5% and 10% BLA exhibited superior mechanical performance compared with the control mix. In particular, the 10% BLA mixture achieved a compressive strength of 33.5 MPa at 28 days, exceeding the target strength requirement. Furthermore, the compressive strength continued to increase at 56 days, demonstrating the contribution of the pozzolanic reaction to long-term strength development. Concrete mixtures containing 5–10% BLA also exhibited lower water absorption and improved resistance to sulfate attack. Although higher BLA contents increased the water demand and prolonged the setting times of cement paste, the overall results demonstrate that BLA can be effectively utilized as a supplementary cementitious material, with an optimum replacement level of 10% for producing durable and environmentally sustainable concrete.