Mechanical and perceptual characterization of ultra-high-performance cement-based composites with silane-treated graphene nano-platelets

Abstract

An ultra-high-performance cement-based composite (UHPCC) with excellent mechanical behaviors and self-perceived properties was successfully prepared in this work. The effects of silane-treated graphene nano-platelets (ST-GNPs) on the fluidity, porosity, degree of hydration, mechanical behaviors, and self-perceived properties of UHPCC were investigated. The results revealed that the fluidity of UHPCC fresh mortar is directly related to ST-GNPs content. The fluidity decreases as the amount of ST-GNPs increases. Furthermore, when the amount of ST-GNPs was 0.05%, the porosity of UHPCC was found to be 11.5%, and the compressive strength and flexural strength reached the maximum value of 142.5 MPa and 23.8 MPa, respectively. Additionally, the microstructure of the UHPCC was investigated. Also, it was indicated that the introduction of ST-GNPs could enhance the transformation of fibrous calcium silicate hydrate (C–S–H) gel into petal-like hydration products, which has the tendency to continuous interpenetration. Further, the introduction of ST-GNPs is confirmed to reduce the resistivity of UHPCC from 18.85 kΩ·m to 6.26 kΩ·m. Finally, the self-perceived performance of UHPCC with 0.05% ST-GNPs was observed to be about double that of UHPCC without ST-GNPs, which indicates that the UHPCC prepared by adding ST-GNPs has excellent self-perceived performance.