Mechanical and durability studies on different grades of concrete using cinder aggregates

Effective waste management in the steel industry is crucial for sustainability. With rising construction costs and the depletion of natural resources, integrating industrial by-products into construction has become increasingly important. Cinder, a significant by-product of steel manufacturing, forms when molten steel separates from impurities in the furnace. This study investigates the impact of cinder on the mechanical performance of concrete, focusing on compressive strength, split tensile strength, and flexural strength after 7 and 28 days of curing, along with microstructural analysis using SEM and XRD. The research explores replacing coarse aggregate with cinder in varying proportions from 0% to 80% in 10% increments to assess its feasibility for sustainable concrete production. The test results indicate that the target compressive strength is achieved with 70%, 50%, and 40% cinder aggregate replacement in M20, M30, and M40 concrete grades, attaining 27.56 MPa, 38.67 MPa, and 49.77 MPa, respectively. Additionally, durability tests, including water absorption and RCPT, were conducted. The charge passed in M20, M30, and M40 concrete with 70%, 50%, and 40% cinder aggregate was 3550.35, 2231.22, and 1936.65 coulombs, classifying them under moderate to low permeability categories, indicating its potentiality to be used in the concrete.