Evaluation of the mechanical propertiesof concrete with added shot blastingwaste

Abstract

The growing demand for sustainable infrastructure projects has prompted the search for alternatives to mitigate the environmental impact generated by the construction industry. In this sense, cement production is recognized as one of the processes with the highest greenhouse gas emissions. In order to reduce the proportion of cement in concrete mixes, this study evaluated the potential of shot blasting dust, a waste product of the metallurgical industry, as a partial substitute for cement in concrete mixes. To this effect, an experimental program was executed that incorporated the preparation and testing of specimens, as well as the subsequent collection and processing of data. Additionally, control samples were evaluated, as well as four replacement proportions (2.5 %, 5.0%, and 7.5%), evaluating both mechanical and durability properties. The results showed significant improvements in compressive, tensile and flexural strength in the added samples, especially with 2.5% and 5.0% shot blasting dust replacements. At 28 days of curing, the mixes with 2.5% replacement achieved a 50.7% increase in compressive strength and reduced permeability to chloride ions, indicating an improvement in concrete durability. On the other hand, although 7.5% substitution showed less pronounced improvements, it represents a more sustainable option by reintroducing greater amounts of industrial waste. This study highlights the importance of using industrial waste such as shot blasting to improve the sustainability of construction, decreasing the carbon footprint and promoting the circular economy in the concrete industry.