Retrofitting Using Geopolymer Mortar: A Strength Study

The body of research reviewed confirms that geopolymer mortars hold substantial promise for the retrofitting of RC structures, offering improved strength, durability, and sustain-ability relative to conventional OPC-based systems. Rapid curing, enhanced chemical resistance, and a markedly reduced environmental impact position geopolymer mortars as a viable mainstream repair material. Realizing this potential, however, requires the following targeted actions: •  Standardized Mix Development: Codified geopolymer mix designs tailored to retrofitting applications are needed to ensure consistent mechanical properties and ease of field application across varying site conditions. •  Enhanced Interface Engineering: Improved surface preparation protocols and interface optimization tech-niques are essential for maximizing bond strength and mitigating shrinkage cracking or debonding in composite systems. •  Pilot Projects and Case Studies: Large-scale pilot projects with long-term observation programs are required to assess geopolymer retrofit effectiveness under diverse climatic, chemical, and loading conditions and to establish credible cost-benefit relationships. •  Code and Guideline Development: Comprehensive design standards and practical field guidelines—addressing curing practices, environmental exposure, worker safety, and seismic resilience—will accelerate mainstream adop-tion. Future research should investigate hybrid systems incorporat-ing natural fibers, nano-additives, or advanced reinforcements to further improve strength and ductility. Integration of real-time structural health monitoring into geopolymer-repaired elements, coupled with lifecycle economic models that move beyond initial cost comparisons, will further support the sustainable deployment of geopolymers in infrastructure rehabilitation.

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