Experimental Investigation on the Strength, Durability and Corrosion Properties of Concrete by Partial Replacement of Cement with Nano-SiO2, Nano-CaCO3 and Nano-Ca(OH)2

Abstract

Present study discusses the role of nano-composite materials to achieve mechanical, durable and corrosion resistance properties of high-strength concrete mixtures. Silicon and calcium-based nano-composite materials such as nano-SiO2, nano-CaCO3 and nano-Ca(OH)2 are replaced in cement in various binary and ternary combinations by varying the dosage 2% and 5% by weight. In addition to the strength performance, specific tests such as water absorption, water sorptivity, permeability, density, coefficient of water absorption, acid penetration, weight loss and the LQR resistance have been further performed to investigate the impact on durability and corrosion resistance. Experimental results showed that the mechanical properties of concrete mixtures have been enhanced (10–45%) due to the presence of nano-materials at their optimum dosage. The optimum dosage of nano-composite materials with cement in the ternary combination was found to be 2% for enhanced mechanical performance and 5% for increased corrosion resistance. However, higher durability results (5% to 60%) were achieved in binary combination with 2% replacement. The improved performance of durability and corrosion resistance was achieved due to the increased surface area of nano-composite materials, which stimulates both pozzolanic reactivity and effective filling of voids in the concrete. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) results have also used to identify the particle distribution in the concrete specimen. The entire investigation shows that the optimum dosage of nano-composite materials gives better performance in concrete specimen.