Mechanical, acoustic and electrical properties of graphene-enhanced mortars

Constructions filled with carbon-based additives are intended to be the next-generation multifunctional materials with advanced mechanical capabilities and ideal smart strain sensing characteristics. Such additives are the graphene nanoplatelets that represent a new class of carbon nanoparticles/nanopowder and consist of small stacks of graphene sheets with an overall thickness of approximately 3-10 nanometers. Their unique size and platelet's morphology make these particles effective at providing barrier characteristics to the supreme applications that are used. The present study has as aim to report on the effect of graphene nanoplatelets presence on mechanical and electrical behavior as well as on the fracture mode of graphene nano-modified cementitious mortars. Pure bending, compression, and fracture tests with the simultaneous acoustic emission monitoring were carried out on specimens fabricated by the introduction of 0 to 1.2 wt. % pure few-layer graphene nanoplatelets in the different mixtures. A suspension for every graphene loading was produced under the ultrasonication procedure. A water-based superplasticizer was selected as dispersion agent based on its efficiency in inhibiting air entrapment inside the specimens and on its chemical stability. As concern the graphene-enhanced mortars the great improvements in mechanical characteristics and also the notable differences in fracture energy of specimens were documented at specific graphene loadings; the improvement was assessed simultaneously by acoustic emission data. In addition, the electrical response of the graphene-modified cement mortars, via the electrical conductivity measurements, is another property that was studied, and the total results are presented and discussed in the present paper.

Automated summary

The study aims to investigate the impact of graphene nanoplatelets on the mechanical and electrical properties of cement mortars. Significant improvements in mechanical characteristics and fracture energy were observed at specific graphene loadings, as evaluated by acoustic emission data. Additionally, the electrical response of the graphene-modified cement mortars was studied through electrical conductivity measurements.