Influence of coal bottom ash on tensile and flexural strength of concrete

Abstract The construction industry faces growing pressure to adopt sustainable practices while ensuring structural integrity. Coal bottom ash (CBA), a by-product of coal combustion, offers a potential sustainable alternative to traditional fine aggregates in concrete. This study examines the impact of CBA on the tensile and flexural strength of concrete, aiming to develop sustainable materials with enhanced mechanical properties. Fine aggregates were replaced with CBA at 0%, 10%, 25%, and 40%. Split tensile and flexural strength tests were conducted after 7, 14, and 28 days of curing. Statistical analysis was performed to assess the significance of CBA content on strength. A 10% CBA replacement led to an 18.7% increase in split tensile strength at 28 days, while flexural strength was maximized with a 40% CBA replacement, resulting in a 33.7% improvement. The findings suggest that incorporating CBA enhances both tensile and flexural strength, with improvements depending on the replacement percentage and curing time. CBA, therefore, has the potential to serve as a sustainable alternative to traditional fine aggregates, offering improved mechanical properties and environmental benefits.