Multifunctional Graphene/Cement-Based Sensors for Structural Health Monitoring

Presented By: Wengui Li, University of Technology Sydney

Graphene nanoplate (GNP) and graphite plate (GP) are promising functional nanofillers for smart cementitious composites. The effects of GNP and GP on physicochemical, mechanical and piezoresistive properties of cementitious composite were investigated in this study. The results show that the cement hydration was accelerated with the increase of GNP and GP because of nucleation effect. The electrical resistivity of GNP-cementitious composites is always lower than that filled with GP at the same concentration. On the other hand, percolation occurs for the GNP/cement composites at the dosages from 2-3% (by weight), while it never happens for the GP/cement composites. Moreover, the GNP/cement composites reached the maximum mechanical strengths when GNP content was 1.0%, while for the GP/cement composites, only minor strength improvement was obtained at a dosage of 0.5% GP. As for the piezoresistivity, the cementitious composites filled with GNP exhibited higher fractional changes of resistivity. Irreversible resistivity generated for 2-3% GP/cement composites subjected to cyclic compression, due to the poor and loose microstructure. Related outcomes can provide an insight into the application of GNP/cement composites and GP/cement composites as cement-based sensors for structural health monitoring.