Recycling of Used Foundry Sand and Fly Ash in Concrete as a Partial Replacement for Conventional Ingredients

Abstract

AbstractThe global population is increasing at tremendous rate. So, the rapid infrastructure development is required to meet the hasty infrastructure demand. Reinforced cement concrete (RCC) is a critical component of infrastructure development. The natural fine aggregate (NFA) which is commonly known as sand, is a crucial concrete component; however, fine aggregate is in short supply due to its excessive use. Moreover, the local authorities have outlawed the extraction of fine aggregate from water bodies to protect the ecosystem. As a result, it is a critical to consider a new supply or substitute material for natural fine aggregate. The current study has designed to replace a specific percentage of natural fine aggregate with used foundry sand with this goal in mind the three experimental scenarios evaluated in this study. Scenario A: A portion of the natural fine aggregate has replaced with used foundry sand (UFS) in proportions of 15%, 25%, and 35%. Scenario B: The mass of cement has replaced with fly ash in the ratios of 15%, 25%, and 35%, respectively, while in Scenario C: The mass of natural fine aggregate and cement is replaced with used foundry sand and fly ash in the proportions of 15%, 25%, and 35%, respectively. In the laboratory, the physical properties of used foundry sand (UFS), fly ash (FA), cement, coarse aggregate (CA), and natural fine aggregate (NFA) have examined. It has inferred that 25% of natural fine aggregate can replaced by used foundry sand successfully; however, over this proportion, the compressive strength of concrete reduces somewhat, and workability decreases. Also, to achieve the desired strength, replacing 25% mass of the cement with fly ash was feasible. The overall result of robust experimentation work shows that Scenario C, i.e., replacement of natural fine aggregate (NFA) with 25% UFS and partial replacement of cement with 25% of fly ash, is a better option to achieve the desired strength with optimum cost. The study suggests that partially substituting alternative resources such as foundry sand and fly ash for traditional concrete ingredients is efficient and viable. The study's findings have a socioeconomic benefit and benefit the protection and maintenance of the natural system. The research will aid in developing a sustainable and efficient concrete mix; moreover, it will strengthen the country's economy.KeywordsUsed foundry sandAggregate replacementFly ashCompressive strengthConcrete