Influence of graphene oxide dispersion strategy on recycled concrete powder for cementitious systems

Closing the loop on construction and demolition waste through high-value recycling is crucial for advancing the circular economy and mitigating the carbon footprint of the built environment. Recycled concrete powder (RCP) is commonly underutilized due to its low hydration reactivity and inherent performance limitations. This study innovatively introduces a new GO dispersion strategy to enhance the performance of the recycled cementitious system. The results show that the application of coating modification methods can reduce porosity by approximately 10.6–22.0 %, increase mechanical strength by 7.7–53.4 %, and significantly enhance the resistance to chloride ion penetration. By leveraging CNN machine learning and DTD pore feature extraction, the enhanced regions of GO were located with an optimal recognition accuracy of 95.9 %, verifying that the coating optimization degree reached 33.2–72.9 %. Critically, the LCA results demonstrate that the GO-modified RCP system significantly reduces greenhouse gas emissions and primary energy demand by 24.37 % and 24.14 %, respectively, highlighting its substantial environmental benefits. This work offers a scalable technological solution that synergistically enhances material performance, resource efficiency, and carbon mitigation, thereby contributing directly to cleaner production and more sustainable construction systems. • GO-coated RCP produces materials with high strength, durability and excellent workability. • Depth analysis of microscopic pore structure based on BSE images and deep learning. • The microstructure optimization effects of GO coating reinforcement are analyzed. • The economic and environmental benefits are evaluated based on LCA theory.