Valorisation of Marine Bio-Waste as a Sustainable Concrete Constituent: Experimental Performance and Predictive Optimization

Abstract

The growing demand for climatic responsive construction materials increased the interest in valorising marine bio-waste as sustainable alternatives to conventional concrete. The study investigates the mechanical and physical performance of concrete cubes incorporating calcium rich marine bio-waste as additives which includes shrimp shell, fish bone, lobster shell, oyster shell, and sea shell at varying percentages. Experimental evaluation was conducted to determine compressive strength, failure load, water absorption, dry density, and wet density of modified mixes in comparison with conventional control specimens. Linear and polynomial regressions are developed for each material category, and multivariable regression models were established to predict strength behaviour. The results demonstrated that strength response is material-dependent and non-linear, with shrimp shell and fish bone mixes exhibiting discernible optimum ranges, whereas lobster shell additions generally led to strength reduction at higher percentages and the optimum dosage is 4%. Multivariable regression incorporating physical parameters achieved up to 70% explanatory capability, establishing the significant influence of density and absorption on strength development. The findings confirm the feasibility of using selected marine bio-wastes as sustainable concrete modifiers, highlight the necessity of material-specific optimization, and contribute predictive analytical tools supporting circular economy-based construction practices.