Production of Structural Concrete and the Effects of Various Waste Materials on Concrete used as Partial Replacements for Cement

Supplementary cementitious materials (SCMs) are additives incorporated into concrete mixtures to enhance their properties and minimize their environmental impact. Common SCMs include fly ash, slag, silica fume, red mud, construction and demolition waste (C&D), and mortar waste. The addition of SCMs in construction practices offers the advantage of reducing the amount of Portland cement needed in concrete production, which is a significant contributor to carbon dioxide emissions, thereby lowering greenhouse gas emissions. Furthermore, the addition of SCMs can improve the durability and performance of concrete, making it a more sustainable option for construction projects.Consequently, the construction industry is actively researching and developing novel materials to further enhance the sustainability of concrete.Various alternatives exist for cement substitution, aiming to enhance the overall quality of concrete without compromising its strength. This research study has been focused on assessing the effects of substituting cement with mortar, red mud, and eggshells in the M25-grade of the concrete mixture. The evaluation involved measuring the compressive strength, flexural strength, split tensile strength, and flexural strength at curing periods of 7, 14, and 28 days. The findings have revealed that the application of these waste materials resulted in superior structural properties of concrete compared to traditional concrete compositions. Additionally, the micro-structural characteristics of different waste materials have been investigated through scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX).