A comprehensive review on self-sensing graphene/cementitious composites: A pathway toward next-generation smart concrete

Two-dimension graphene-based nanomaterials (GBNs), such as multi-layers graphene (GNPs) and graphene oxide (GOs) have been extensively applied to enhance the mechanical properties, durability, and self-sensing performance of construction materials. Although there are some reviews on the mechanical properties and durability of graphene-based cementitious composites (GBCCs), very few papers have comprehensively covered the nano-, micro- and meso-scale properties, components, structures, and self-sensing properties, and the applications of the GBCCs. In this review, the characteristics of various GBNs with different dimensions were firstly illustrated and compared, and the enhancement methods for dispersion of 2D GBNs before mixed with cementitious materials were also comprehensively compared and discussed. When GBNs were mixed with cement, the nano- and micro-scale characteristics of GBCCs with respect to the hydration, phase transformations, microstructures, and pore characteristics were also systematically discussed. Macroscale performances of GBCCs, such as rheology, flowability, mechanical strength were analyzed, and the durability performances (e.g. chemical and fire attack, shrinkage and transport properties) of GBCCs were evaluated correspondingly. On the other hand, the self-sensing properties (e.g. electrical resistivity, piezoresistivity, and electromagnetic properties) of GBCCs were assessed for potential practical applications for structural health monitoring (SHM). Furthermore, some case studies and applications of GBCCs as advanced cement-based sensors for SHM were also evaluated. Finally, the application challenges and perspectives of adopting 2D GBNs for smart and sustainable concrete structures were proposed and discussed correspondingly. The conclusions of this review will promote future researchers and civil engineers in the concrete-related industry with the aim to developing sustainable and functional graphene-based concrete for the next-generation smart infrastructure.