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@article{206989,
        author = {Varun G and Dr. D. Shoba Rajkumar and V. Chandrikka},
        title = {Microstructural Analysis of Crumb Rubber Concrete Using Scanning Electron Microscope},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {2},
        pages = {3309-3312},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=206989},
        abstract = {The utilization of waste tyre rubber in concrete has emerged as an environmentally sustainable approach to reducing solid waste while conserving natural aggregates. However, the incorporation of crumb rubber modifies the internal microstructure of concrete, thereby influencing its mechanical and durability characteristics. This study presents a microstructural investigation of M30 grade crumb rubber concrete using Scanning Electron Microscope (SEM). Concrete specimens containing crumb rubber as a partial replacement for coarse aggregate were examined to evaluate the morphology of hydration products, pore distribution, interfacial transition zone (ITZ), and crack formation. SEM observations revealed that conventional concrete exhibited a relatively dense microstructure with well-developed calcium silicate hydrate (C–S–H) gel and fewer micro voids. In contrast, crumb rubber concrete showed localized voids and weaker bonding at the rubber–cement interface due to the hydrophobic nature of rubber particles. Nevertheless, the incorporation of steel fibres improved crack-bridging behaviour and enhanced the compactness of the cement matrix. The microstructural observations correlated well with the experimentally observed mechanical behaviour, indicating that optimized crumb rubber concrete can provide improved ductility while maintaining satisfactory structural performance. The study demonstrates the significance of SEM analysis in understanding the internal behaviour of sustainable concrete materials.},
        keywords = {Crumb Rubber Concrete, Scanning Electron Microscope, Microstructure, Steel Fibre, Hydration Products, Sustainable Concrete.},
        month = {July},
        }