Application of Graphene Oxide in Ordinary Concrete Materials: Modification and Performance Optimization

Concrete, as a widely used construction material, suffers from performance degradation due to chloride penetration and sulfate attack in harsh environments. Conventional performance-enhancing methods are costly and emit high levels of carbon dioxide. This study modified graphene oxide (GO) with polycarboxylate superplasticizer (PCE) alone or PCE synergized with a rubber viscosity reducer, optimized dispersion (50 °C water bath for 1 h), and prepared C50 modified concrete (500 kg/m3 cementitious materials, w/b = 0.33). GO contents were 0%, 0.001%, 0.003%, 0.005%; a group with 8% reduced cementitious materials (460 kg/m3) was also tested. Results showed PCE-viscosity reducer synergy better dispersed GO, improving concrete workability. GO accelerated cement hydration via nucleation, refining C-S-H gel and reducing porosity. At 0.005% GO, 56 d drying shrinkage dropped by 29.3% vs. the blank, and 56 d chloride penetration electric flux was 586 C, meeting 100-year service life. Sulfate resistance also improved with higher GO content. Even with 8% less cementitious materials, modified concrete outperformed the blank. This provides support for GO’s application in cement-based materials.