Mechanical performance and corrosion resistance of reinforced concrete with marble waste

In this work, the performance of reinforced concrete containing different percentages of marble filler as a partial substitution of ordinary Portland cement is investigated. The cement is replaced by marble accordingly in the range of 5, 10, 15 and 20 wt.% for concrete. The measurements of flexural and compressive strengths are conducted on the concrete with marble dust. The corrosion behaviour of reinforced concrete in the aggressive medium (3% NaCl) is carried out using the potentiodynamic polarisation and impedance spectroscopy. From the outcome of this investigation, the partial substitution of cement by up to 20% of marble in concrete is achieved without compromising the overall strength. For all mixtures, the maximum compressive and flexural strengths at all curing ages are obtained with a 5% replacement of cement by marble. The greater effectiveness of marble waste is attributed to its higher calcium content and CO3 (2-) ions release, which lead to the formation of carboaluminate hydrates, then to further porosity reduction that increases the strengths. The results also show that the steel bars in reinforced concrete prepared with 5% of marble have better corrosion to that in the ordinary reinforced concrete.