Optimization of Periwinkle Shell Ash and Sawdust Mixture as Additives in Fired Clay Brick Using Grey Relational Analysis in Taguchi Methodology

Abstract

The use of additives remains one of the methods of enhancing compressive strength and thermal conductivity of a clay bricks used for various applications in the construction industry. However, obtaining the right mixtures of additives remain a concern by most researchers. In this study, an experimental and modelling approaches were used to determine optimum mixture of periwinkle shell ash (PSA) and sawdust (SD) additives at 5-20 % by weight at 900-1100oC firing temperature on fired bricks. The objective of the study was to evaluate the thermo-mechanical properties of the additives with a view to minimizing thermal conductivity and enhancing compressive strength. Consequently, an optimal thermal conductivity of 0.3486 W/mK was obtained for the additives using a control factor setting of SD10PSA15FT1100. In case of an optimum value for a compressive strength, a value of 8.2234 MPa was obtained employing a control factor setting of SD10PSA10FT1100. The estimated values obtained in the present study aligned with the suggested thermal conductivity of less than 0.6 W/mK and the proposed minimum compressive strength of at least 7 MPa. This fulfils the "Lower the Better" and "Higher Better" criterion for thermal conductivity and compressive strength respectively. In addition, a close relationship between predicted and experimental values of thermal conductivity affirmed the acceptance of the prediction model with an R-squared value of 96.25%. Conversely, as for the compressive strength, the predicted and experimental values exhibited a close relationship where the prediction model also boasts an R-squared value of 89.93%, signifying its strong acceptability for accurate predictions. The present study will be utilized in optimizing the quantity of additives used in the production of clay fired bricks for various industrial heat containment and eco-friendly applications.