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This study aims to identify the micro-cracking pattern and structural applications of cement composites replaced with 0 wt%, 0.04 wt%, and 0.08 wt% contents of graphene nanoplatelets (GNPs) over cement weight through acoustic emission (AE) monitoring under mechanical degradation. The ultraviolet-visible spectroscopy (UV–vis) results showed that at 60 min sonication period, GNP-4 showed maximum absorbance rate of 16.15% compared to the GNP-8. The microstructural characteristics revealed that during hydration of cement there was no apparent cracks appeared in GNPs-cement composites compared to the reference specimen (GNP-0) which was 1.44 mm. The cracking mode and damaged detection of the tested specimens resulted in three distinct stages i.e., (I) pre-peak, (II) peak, and (III) post-peak under mechanical degradation. GNP-4 achieved 780 N flexural capacity which was increased by 30% and 21.87% compared to the GNP-0 and GNP-8. Similarly, a compressive strength of 63.12 MPa, 57.5 MPa, and 56 MPa at 28 days was obtained by GNP-4, GNP-8, and GNP-0, respectively. Based on AE hits and amplitude analysis, the resistance to fracture, damping capacity, and ductility of GNP-4 was improved by 25.30%, 25.1%, and 22.47% respectively, to that of GNP-0. Shear failure (>35 kHz) was observed in GNP-0, while GNPs cement composites recorded tensile failure ( |
