Multi-walled carbon nano-tubes for enhancing the performance of cementitious composites

Abstract Due to exceptional properties, multi-walled carbon nano-tubes (MWCNTs) are designated as a promising reinforcing material for the nano-modified cementitious composites. The performance of cementitious composites with MWCNTs on the mechanical, durability, and microstructure properties was investigated in this study. The MWCNTs were effectively dispersed by the sonication method using high-frequency ultrasonic waves. The flexural strength, compressive strength, density, porosity, and stress-strain curves of cementitious composites reinforced with different concentrations (0.1, 0.2, 0.3, 0.4, and 0.5 wt%) of MWCNTs were studied. The enhanced flexural and compressive strength demonstrates the exceptional reinforcing behaviour of the MWCNTs. Additionally, density outcome indicates that as the percentage of MWCNTs in the matrix increases, density increases, and the optimum content was obtained as 0.3 wt%. The pores of cementitious composites can be reduced by adding carbon nano-tubes, which was perceived through a microstructural study using SEM micrographs. Study outcomes establish that in addition to the advantages provided by the nano-tube reinforcement in augmenting strength, nano-tubes can also help in reducing the porosity of the composites. The effectiveness of this promising nanomaterial related to its field application is also highlighted.