Piezoresistive Behavior and Applications of Graphene Oxide-Modified Concrete: Experimental and Simulation Study

To enable self-sensing capabilities in concrete structures for real-time health monitoring, this study investigates the incorporation of graphene oxide (GO) to develop smart concrete. The mechanical, electrical, and flexural-sensing properties of GO-concrete were systematically examined at both material and structural levels. The core finding of this research is the identification of an optimal GO content (0.09%) and the successful demonstration that a layered configuration of GO-concrete within beams functions as an excellent flexural sensor, providing precise electrical signal feedback for deformation and damage. Experimental results indicate that at this optimal content, the compressive strength and electrical conductivity were significantly enhanced, with a 17.67% increase in strength and a 32.28% decrease in initial electrical resistivity. Microstructural analysis revealed that this improvement stemmed from more complete cement hydration and reduced porosity. At the structural level, while GO had a negligible impact on the flexural load-bearing capacity of beams, it substantially improved the electrical resistivity’s responsiveness to applied load and deflection. The beam with a layered GO configuration exhibited the highest signal correlation. Furthermore, finite element simulations agreed well with experimental findings, revealing that the resistance change is intrinsically linked to crack propagation, which alters the length and cross-sectional area of the current path. This confirms the reliability of this material for structural monitoring applications.