Carbon nanotube reinforced cementitious composites: An overview

In the construction sector, interest and exploration work within the field of carbon materials have been ongoing for many years. Although carbon fibers have already been applied to cementitious composites, carbon nanotubes (CNTs), as nanomaterials, have received widespread attention as a result of their unique multifunctional properties within the context of engineered materials. This article focuses on the research advances of CNT dispersion and CNT reinforcement on the mechanical, electrical and piezoresistive properties of cementitious composites. Sonication and surfactants, as the commonly used techniques for CNT dispersion, are introduced for CNT/CNT dispersion characterization. Four reinforcing mechanisms of CNTs in cement matrices are summarized. Various factors that work towards an effect on the mechanical, electrical and piezoresistive properties of CNTs are reported, including CNT size, CNT concentration and lattice defects on the CNT structure. In addition, the effect of CNTs on the workability, hydration process and autogenous shrinkage of cement paste are discussed.