Influence of Biochar Content and Curing Methods on the Physical And Mechanical Properties Of Non-Autoclaved Aerated Concrete

Abstract

This study investigated the effects of biochar content and curing methods on the properties of non autoclaved aerated concrete (NAAC). Cement was partially replaced with biochar at varying percentages (0%, 2.5%, 3.5%, and 5%), and the resulting samples were subjected to steam curing, moist curing, and carbonation curing. The primary objective was determining the optimal conditions for enhancing NAAC's performance in bulk density, compressive strength, and drying shrinkage. Results indicate that both biochar content and curing method significantly influence NAAC properties. Bulk density increased with biochar content up to 3.5% for steam and moist curing, subsequently decreasing slightly at 5%. Steam curing generally produced higher bulk densities than moist curing, demonstrating its effectiveness in optimizing NAAC density. Compressive strength followed a similar trend, with the highest strength achieved at 3.5% biochar for both curing methods. Steam curing consistently yielded superior compressive strength values compared to moist curing, suggesting its potential for enhancing NAAC's structural integrity and suitability for load-bearing applications. Drying shrinkage increased with biochar content up to 3.5% for both curing methods but decreased at 5%. However, steam curing generally resulted in higher shrinkage values than moist curing. Overall, this study underscores the importance of carefully selecting biochar content and curing methods to optimize NAAC performance. Steam curing is a promising approach for improving bulk density and compressive strength, although it may lead to increased drying shrinkage.