The Effect of Multi-Wall Carbon Nanotubes on the Flexural and Compressive Strength of Cement-Based Composites

Nanoparticles are characterized as the most frequently used materials for embellishing the nanomodified specimens’ multifunctional characteristics. The combination of cementitious composites with nanomaterials is important for enhancing the microstructural characteristics of cement-based materials and filling voids in the cement pastes. Recently, many studies on incorporating carbon nanotubes in cement paste showed an improvement in the engineering field. In this research, many three-point bending tests into prismatic samples that were cast into molds conducted to examine the multi-wall carbon nanotubes’ (MWCNTs) mechanical characteristics. More specifically, for creating cement paste enhanced with MWCNTs, three different amounts of MWCNTs, such as 0.1 wt.% MWCNTs, 0.2 wt.% MWCNTs, and 1.0 wt.% MWCNTs of cement were applied. Sonication energy and surfactants were applied in order to disperse the MWCNTs into the aqueous solution. By evaluating the results, it was concluded that the amount of 0.1 wt.% MWCNTs revealed the best mechanical properties, such as 55.5 MPa 28-day compressive strength and 6.9 MPa flexural strength compared to the other samples. Thus, MWCNTs are capable of creating cement-based materials with multiple structural functions.