Enhancing flexural performances of cement composites by functionally graded distribution of graphene nanoplatelets: Finite element modeling and experiment

Graphene nanoplatelets (GNPs) are recognized as highly effective nano‐reinforcements for improving the mechanical performances of cement composites. However, optimizing their spatial distribution remains a key challenge for maximizing the reinforcing efficiency. This study presents a comprehensive investigation on functionally graded (FG) GNP reinforced cement composites (GNPRCCs) by combining finite element modeling (FEM) with experiments. The developed FEM framework, which incorporates concrete damage plasticity (CDP) and cohesive contact models, accurately predicts the flexural behaviors of the cement composites, which are validated by experiments. A 45.56% increase in the flexural strength is achieved when only 0.1 vol% GNPs are added into the cement matrix. Parametric analysis demonstrates that both the diameter‐to‐thickness ratio ( λ ) and orientation of GNPs play critical roles in reinforcing efficiency, with optimal performance achieved at a ratio of λ = 500 and 45° orientation. In addition, FG distribution strategies result in up to a 137.5% increase in peak load compared to those with uniform distributions of GNPs. These validated FG distribution strategies offer useful guidance for the design and optimization of high‐performance cement composites.