Graphene-Modified Concrete: Influence of Different Graphene Derivatives on Electrical Resistivity Performance

Concrete is the most widely used construction material worldwide; however, conventional concrete lacks intrinsic monitoring capabilities for assessing structural condition during service life. Graphene-based nanomaterials have attracted considerable attention due to their exceptional electrical conductivity and potential application in self-sensing concrete systems. This study investigates the influence of three graphene derivatives, namely single-layer graphene (SLG), few-layer graphene (FLG), and multi-layer graphene (MLG), on the electrical resistivity performance of concrete.

Concrete specimens incorporating graphene were prepared using Ordinary Portland Cement and cured for 28 days under controlled laboratory conditions. Electrical resistance measurements were performed using a four-wire sensing method before and after compression loading. Ultrasonic pulse testing was conducted to evaluate internal structural integrity and microstructural changes.

The results showed that FLG exhibited the lowest initial electrical resistance of 7.20 kΩ, compared with 7.50 kΩ for MLG and 8.20 kΩ for SLG. Following compression loading, electrical resistance decreased by 2.78%, 4.00%, and 10.98% for FLG, MLG, and SLG, respectively, demonstrating the piezoresistive behaviour of graphene-modified concrete. Ultrasonic measurements revealed that FLG experienced the smallest increase in transit time (2.10%), indicating superior resistance to microstructural deterioration, whereas MLG exhibited the greatest increase (7.12%). 

The findings suggest that FLG provides the most effective balance between conductivity, dispersion quality, and structural stability. Consequently, FLG-enhanced concrete shows strong potential for structural health monitoring applications and the development of next-generation smart infrastructure systems.