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@article{194568,
        author = {Oba Achemie L. and Amadi. Patience N.},
        title = {A Comparative Evaluation of Physical and Mechanical Properties of Marine Shells as Sustainable Aggregates in Pavement Construction},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {10},
        pages = {4541-4548},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=194568},
        abstract = {This study investigated the physical and mechanical properties of four marine shell types—Oyster, Whelk, Octopus, and Periwinkle to assess their suitability as sustainable aggregates in construction applications. Comprehensive laboratory tests were conducted including gradation analysis, flakiness index, specific gravity, water absorption, and soundness (using both magnesium and sodium sulfate solutions). Results showed material characteristics among the shell types. Oyster shells exhibited poor gradation (88% retained at 50mm), extreme flakiness (76.4%), low specific gravity (2.05), very high water absorption (10.95%), and moderate soundness (3.6 - 8.2% loss). Whelk shells showed bimodal gradation, excellent particle shape (0% flakiness), moderate specific gravity (2.31), moderate water absorption (5.9%), and excellent magnesium sulfate resistance (2.6% loss). Octopus shells demonstrated well-graded distribution, low flakiness (6.2%), moderate-high specific gravity (2.52), low water absorption (3.85%), and disproportionate soundness—excellent in sodium sulfate (3.0% loss) but poor in magnesium sulfate (10.0% loss). Periwinkle shells displayed uniform gradation (81% at 19mm), excellent shape (0% flakiness), very low specific gravity (1.6), low-moderate water absorption (4.05%), and consistent soundness (8-9% loss). When assessed against construction standards, Whelk, Octopus, and Periwinkle shells met flakiness and water absorption requirements, while Oyster shells exceeded limits. From our findings, Whelk shells are recommended for structural concrete, Periwinkle shells for lightweight concrete applications, Octopus shells for sodium-rich environments, and Oyster shells as cement replacement in powdered form. This study demonstrates that marine shells offer viable, sustainable alternatives to conventional aggregates, supportive of eco-friendly economy principles while reducing environmental pollution.},
        keywords = {Marine shells; aggregates; gradation; flakiness index; water absorption; soundness; construction; concrete},
        month = {March},
        }