Optimum mix ratio for carbon nanotubes in cement mortar

摘要

Cementitious composites have high compressive strength and modulus of elasticity, but relatively low tensile strength, toughness and ductility. They are amenable to enhancement through nanotechnology due to the physical behavior and size of hydration products. Carbon Nanotube (CNT) is a very efficient reinforcing agent due to its extremely high aspect ratio and ultra-high strength. So, there is a high potential to utilize CNT in producing new cement based composite materials. In this study, a parametric experimental investigation was undertaken to determine optimum mix dosage of CNT for cement mortar. Different dosage rates of surface treated Multi-Walled Nanotubes (MWNT), water/cement ratios and plasticizer amounts (as surfactant for the MWNT) were investigated through compressive and flexural strength determinations. A mixing technique was proposed to address the issues related to dispersion of nanotubes within the cement matrix. The proposed mixing technique and design mix significantly enhanced the compressive and flexural strengths, as compared to control samples with no MWNT.