Experimental assessment of graphene nanoplatelet modified paver blocks for mechanical and durability enhancement at low dosages

This research evaluated the impact of adding graphene nanoplatelets (GNPs) in small amounts, ranging from 0 to 0.04 wt% of cement, on the mechanical and durability characteristics of cement paver blocks. The GNPs were dispersed in water using a lignosulfonate/polycarboxylate superplasticizer and mixed through a standardized water-phase process. Testing was conducted in accordance with ASTM standards, including compressive strength (ASTM C39), flexural strength (ASTM C78), water absorption (ASTM C642), and sulfate resistance (ASTM C1012). Each test result represents the average of three samples per mix, ensuring statistical reliability. At a GNP concentration of 0.04 wt%, flexural strength increased by 40%, compressive strength improved by 28% compared to the control mix, and water absorption decreased by 38%. Sulfate-induced expansion and mass change were reduced by up to 15% (all p < 0.05). These enhancements are attributed to improved hydration, microcrack bridging, and pore refinement due to the well-dispersed multilayer GNPs. The findings suggest that even at low concentrations, GNPs can significantly boost the strength and durability of concrete without compromising workability, supporting their potential for scalable use in precast paving applications. These results are consistent with previous studies indicating that the chemistry and dispersion quality of graphene are vital for optimizing performance in cementitious composites [1].