Role of carbon nanotube in reinforcing cementitious materials : An experimental and coarse-grained molecular dynamics study

One-dimensional carbon-based nanomaterials, such as carbon nanotube (CNT) or carbon nanofiber (CNF) have been regarded as ideal candidates to form nanocomposites for the fabrication of high-performance cementitious materials. Although CNT, CNF and nanocellulose possess different mechanical properties, the mechanical enhancement of CNT, CNF or nanocellulose reinforced cementitious falls in a similar magnitude compared with plain cement paste, which should be highly related to the interaction between the nanomaterials and cement hydration products. In this study, CNT has been chosen as a representative nanomaterial to investigate the role in reinforcing cementitious materials in the nanocomposite system through an experimental and coarse-grained molecular dynamics approach. The findings suggest that the CNT changes the fracture process in cement matrix when the microcracks initiate with the significantly improved fracture energy, leading to the improved global mechanical properties, and a nanoscale interfacial transition zone is found that governs the failure of the nanocomposite system.