Application of statistical analysis to evaluate the corrosion resistance of steel rebars embedded in concrete with marble and granite waste dust

In recent years, the production of waste materials has increased due to the growth of industrial activities around the world. Therefore, recycling and reusing these waste materials for different applications would make a tremendous contribution to waste elimination and sustainable building construction. The objective of this paper is to investigate the effect of marble and granite waste dust (MGWD) as a result of marble and granite stone processing on concrete properties. To achieve this purpose, a total of 15 mixes were prepared with up to 30% of MGWD cement replacement. After 28-day immersion of specimens in lime-saturated water, they were placed in a NaCl solution with 3.5% by weight for 90 days. Then, splitting tensile and compressive strength, scanning electron microscopy (SEM), open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) tests were performed alongside a statistical analysis. The mechanical results indicate that utilizing MGWD as cement replacement at a maximum amount of 20% does not notably influence the mechanical properties of concrete. The OCP assessment revealed that using 10% of granite and 10% of marble waste dust instead of cement enhances the corrosion resistance of steel rebars embedded in concrete, and also increases the potential compared to the other tested concrete mixes.