A step towards sustainability to optimize the performance of self-compacting concrete by incorporating fish scale powder: A response surface methodology approach

The depletion of natural resources and the scarcity of non-renewable resources have highlighted the importance of using biomaterials efficiently. Globally, the fishing and aquaculture industries generate a significant amount of waste, including fish scales. Estimates suggest that between 7.2 and 12 million tons of fish waste are produced each year, with a considerable portion being fish scales. Numerous studies have shown that fish scales have potential uses for cleaner production in various industries. There is no past study on the impact of this sustainable and eco-friendly biomaterial in concrete. To fill this gap, this study aimed to add fish scale powder to self-compacting concrete to maximize its performance. A secondary cementitious material containing fish scale powder was employed in the present study at dosages ranging from 1 to 4% and water-to-cement ratios ranging from 0.4 to 0.6. Response surface methodology (RSM) was used to design the experimental mixtures and to augment and estimate the statistical models for predicting the rheological and mechanical properties. In accordance with the EFNARC specifications, all of the mixtures were found to have acceptable rheological properties. In terms of the compression strength, there was a nominal reduction, whereas the tensile strength and flexural strength improved. The RSM models developed had high accuracy, and the optimized content of fish scale powder was found to be 1.87% with a water/cement ratio of 0.5 and a 78.58% desirability. Overall, using fish scale powder as a biomodifier for self-compacting concrete holds promise and feasibility. Repurposing fish scales reduces the environmental impact and creates new revenue streams, promoting sustainability.