Environmental Assessment of Admixtures and Stone Powder in Cement Concrete

Concrete, being a versatile building material, is employed in a wide range of applications. Under normal circumstances, it performs satisfactorily but deteriorates under extreme situations. To attain the desired characteristics during construction, admixtures are used in cementitious materials. Accelerating admixtures fasten the setting and development of early age strength of the cement composites. Stone, on the other hand, is another significant building material used in the construction industry. The stone industry is also expanding with the construction industry's rise, generating tonnes of debris every year. Stone wastes in various forms, such as slurry, dust/powder, broken slabs, and aggregates, have been dumped on valuable land and watersheds. It creates a nuisance to the ecosystem, thereby becoming a potential environmental threat. In the present study, stone powder, along with accelerating admixtures has been utilized in concrete mixtures to examine its feasibility in terms of ecological and economic aspects. The study aimed to investigate the environmental impact of different additives i.e., stone powder, calcium nitrate, and triethanolamine individually and in combination for various cement concrete mixes. The environmental impact of concrete mixtures was evaluated in terms of embodied energy, carbon footprint, and cost analysis of different concrete mixes and compared with the plain mix. The performance index of different mixtures of concrete was also assessed. Results showed that stone powder was found to be very efficient in lowering the cost, energy use, and CO2 emission among all additives. Compared to other additives, using stone powder in concrete enhanced the performance effectively.