Structural Strengthening of Reinforced Concrete Beams Using Ambient-Cured Geopolymer Repair Mortar

The growing body of research on geopolymer mortars for retrofitting reinforced concrete (RC) structures highlights their significant potential in terms of strength, durability, and environmental performance. These materials provide a sustain-able alternative to ordinary Portland cement (OPC) systems, offering benefits such as rapid curing, enhanced chemical resistance, and a lower carbon footprint. However, achieving widespread adoption and consistent performance will require continued research and the development of standardized prac-tices. •  Standardized Mix Development: There is an urgent need to develop codified and field-tested geopolymer mix designs specifically tailored for retrofitting applications. Such formulations should ensure predictable mechanical properties, compatibility with substrates, and ease of application in diverse site conditions. •  Enhanced Interface Engineering: Improved surface preparation techniques and interface optimization are es-sential to enhance long-term bond strength and minimize shrinkage-induced cracking or delamination in composite systems. •  Pilot Projects and Case Studies: Large-scale pilot applications and long-term monitoring are required to evaluate the performance of geopolymer-based retrofits under varying climatic, chemical, and loading environ-ments. These studies will also help establish cost-benefit models over the lifecycle of the structure. •  Code and Guideline Development: Development of comprehensive design standards and practical field guide-lines will facilitate the adoption of geopolymer mortars in mainstream civil infrastructure repair. Codes should address issues such as curing practices, environmental exposure, worker safety, and seismic resilience. Future research should explore hybrid systems that incorpo-rate natural fibers, nano-additives, or advanced reinforcements to further improve strength and ductility. Incorporating real-time structural health monitoring into geopolymer-repaired systems, along with developing comprehensive economic models that consider lifecycle performance rather than just initial costs, will help promote the sustainable and efficient use of geopolymers in infrastructure rehabilitation.

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