Experimental Modelling and Multi-Response Optimization of Fly Ash Carbon Black Bricks for Sustainable Construction Applications

Sudagani Venkata Giri Babu, Sankranthi Krishnaiah

Abstract: Conventional clay brick manufacturing contributes significantly to environmental degradation due to excessive soil consumption and high energy demand. The use of industrial by-products such as fly ash and carbonaceous residues offers a promising alternative for sustainable masonry production. In this study, Fly Ash Carbon Black (FCB) bricks were developed using a Taguchi L27 experimental design to systematically evaluate the influence of material composition on compressive strength, water absorption, and green density. Statistical analysis through signal-to-noise ratios and ANOVA was employed to identify dominant factors affecting performance. A hybrid CRITIC-CODAS multi-criteria framework was further adopted to determine the optimal mix considering mechanical strength, durability, and density simultaneously. The optimized composition demonstrated improved structural behaviour with controlled moisture absorption while maintaining lightweight characteristics. The findings highlight the potential of carbon black as a functional additive in fly ash bricks and provide a structured methodology for developing environmentally responsible construction materials.

Keywords: Fly Ash (FA), Carbon Black (CB), Taguchi L27, ANOVA, CRITIC-CODAS, Sustainable Bricks