The influence of graphene nanoplatelets’ content on sustainable concrete mechanical properties and microstructure

This paper investigates the effect of Graphene Nanoplatelets’ (GNPs) content on sustainable concrete mechanical properties and microstructure. Aqueous solutions were prepared using a wet-dispersion technique to disperse GNPs in the mixing water. Concrete batches were prepared using GNPs-to-cement ratios of 0.05, 0.1, 0.25, 0.5, 1 and 2 %. The 28 day compressive, flexural, and tensile strengths of the prepared specimens were then determined. Moreover, specimen qualitative microstructural analyses were performed using a Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray (EDX). The results obtained were then analyzed using ANOVA method that demonstrated improvements in all strength properties when using GNPs’ filaments regardless of their weight fraction. The batch containing 0.5 % GNPs had the largest strength improvements where the mix of compressive, flexural, and tensile strength properties could be improved by 22.6%, 23.9% and 255.4 %, respectively. The microstructure analysis showed a good dispersion of nanofilaments inside the concrete matrix using the dispersion technique utilized in this study. Finally, the ANOVA analysis reveals statistically significant relationships between the GNPs’ content ratio and compressive, flexural, and tensile strengths in the concrete samples. The results highlight the importance of the GNPs’ content ratio in influencing the concrete's mechanical properties.