Thermal Insulation Enhancement of Metakaolin-Based Geopolymer Concrete Using Waste Clay Brick

Abstract

Geopolymer concrete is one of the sustainable building materials that has a low energy production and a minimum carbon footprint. In this study, the effect of utilization waste clay brick on the thermal conductivity (TC) of Metakaolin geopolymer concrete (MK-GPC) was investigated. The waste of clay brick was used in two series of mixes, first one included clay brick waste powder (BP) as partial replacement of Metakaolin (MK) at weight dosage 10%, 15%, and 20%, while the second group of mixes contained crushed clay brick waste aggregate (CBA) at replacement level of 10%, 20% and 30% by volume of natural coarse aggregate. In addition to (TC), all the specimens were tested to determine the ultrasonic pulse velocity (UPV), and voids content at 7 and 28 days. The results of the samples with 10% and 15% BP have shown higher UPV and less voids content, while the incorporation of CBA aggregate at 20% and 30% caused reduction in UPV and increased the voids in MK-GPC mixture. Furthermore, the addition of the waste clay brick in both forms (powder and aggregate) has improved the results of thermal insulation. Conclusively, reusing of waste clay brick as ingredients in MK-GPC will provide a super-sustainable geopolymer concrete with advanced thermal insulation properties.