Estudo das propriedades físicas e mecânicas de argamassas reforçadas com nanotubos de carbono

Abstract

Nanotechnology is currently considered one of the most promising branches in the scientific field. Carbon nanotubes (NTCs) are one of the newest discoveries in this field, and recent research in the field of civil construction indicates that this material can act effectively as reinforcement of structures. NTC, because of its high tensile strength, can become an important component in the manufacture of concrete and mortar that requires good performance in said property. NTC applications are delimited due to their price. Currently, this value is still high, which hinders the incorporation of NTC in large proportions in civil construction materials. In this sense, this study aims to evaluate the effects of the incorporation of NTCs on the physical and mechanical properties of Portland cement matrices. The NTCs were added to the mortars in the form of dispersion, in the contents of 0.20%, 0.30% and 0.40%, relative to the mass of cement. For the mortars in the fresh state, the consistency index, mass density and incorporated air content were determined. The evaluation of the mechanical properties of the mortars was measured by tests of tensile strength in flexion and axial compression. The physical properties of the mortars were analyzed by the capillary water absorption test. Mortars with addition of NTCs, when compared to the reference mortar, showed improvements in all the properties analyzed in the present study. Even with the improvements observed, there are some challenges to be faced for the use of large-scale NTCs in cement matrices, such as high material cost and difficulty in ensuring efficient dispersion in the mix.