Synergistic Influence of Vindhyan Sandstone Manufactured Sand and Rice Husk Ash on Concrete Performance

Environmental sustainability and the mitigation of greenhouse gas emissions are paramount concerns on a global scale. Incorporating RHA in concrete addresses both environmental issues and agricultural waste disposal, simultaneously reducing CO₂ emissions. Additionally, rapid construction growth has led to excessive RS mining, damaging ecosystems and raising costs, making M-sand a viable alternative. This study evaluates the impact of RHA and VS M-sand as partial replacements for OPC and RS in concrete. RHA content ranged from 0 to 25% and VS M-sand up to 50%. Optimal strength and durability were achieved with 15% RHA and 50% VS M-sand. RHA (0–15%) enhanced strength and sulphate resistance, but performance declined beyond 15% content. SEM analysis revealed a dense CSH gel structure in the 15% RHA and 50% VS M-sand mix. This research underscores the potential of RHA and VS M-sand as sustainable alternatives in concrete production, promoting environmental preservation and resource management.