A systematic review on the engineering properties of concrete with carbon nanotubes

The incorporation of carbon nanotubes (CNTs) into cementitious matrices, and more specifically to concrete, has enhanced their strength and durability. With this perspective, this manuscript aims to review the main engineering properties of concrete with carbon nanotubes (CNT-concrete). To this end, ProKnow-C methodology was used to find the most relevant papers published in the last five years, and 19 articles were selected for a complete analysis. The data collected were the CNT type, content, and dispersion technique, as well as CNT-concrete type and properties, namely the compressive, tensile, and flexural strength, elastic modulus, water absorption, porosity and permeability, electrical conductivity and resistivity, carbonation and chloride penetration resistance, and fracture energy and toughness. This systematic review of the literature revealed that CNT addition generally enhances concrete strength, but its influence on other engineering properties, such as carbonation and chloride penetration resistance, creep and shrinkage, still requires further investigation.