Strain-rate sensitivity of cement composites: Insights from field's metal nano-inclusions

In this study, we investigated the effects of Field's metal (FM) nanoparticles (NPs) on the mechanical behaviour of cement paste under quasi-static (QS) and dynamic strain rates. We found the highest mechanical improvement under QS loading with 1 % FM dosage, beyond which boosting the dosage diminished its contribution to the mechanical performance. Conversely, under dynamic loadings, boosting the dosage from 1 % to 4 % FM significantly and progressively enhanced the overall mechanical performance. These results indicated that the mechanical impacts that ensue from the microstructural modification effects of FM differ with dosage and strain rates. Under QS loading, the pore-refining effect of the NPs was predominant, whereas, under dynamic loadings, the reinforcing effect of the NPs was the primary factor. Furthermore, by comparing the effects of FM and nanosilica NPs, our findings underscored the pronounced effect of the nanomaterial physical and mechanical properties on the strain-rate sensitivity of cementitious nanocomposites.