Improvement Of Heat Conductivity Coefficient Of Fly Ash-Based Geopolymer Brick By Substitution Of Blast Furnace Slag

Abstract

Brick, one of the oldest materials known in history, is a building material that has come up to the present day by continuing its development over time. However, with the development of technology, the brick has been continuously revised. Recently, researchers have turned to the production of geopolymer bricks by substituting waste materials into the brick structure.
 In this study it is aimed to research the effect of blast furnace slag substitution on the heat conduction coefficient of fly ash-based geopolymer brick. In the study, blast furnace slag was replaced with clay in different proportions (10, 30, 50, and 70%). Furthermore, 20% of the fly ash was kept constant, 8 and 10 M of sodium hydroxide for alkaline activation, and 4% and 8% of calcium hydroxide were used to produce geopolymer bricks.
 The heat conductivity coefficient determination experiment was applied to the samples. As a result, it was observed that the heat conductivity coefficient decreased with the increase of blast furnace slag, sodium hydroxide, and calcium hydroxide substitution. The best results were obtained from brick samples produced from 70% blast furnace slag, 10 M sodium hydroxide, and 8% calcium hydroxide with 0.26 W/mK. In addition, it has been concluded that geopolymer brick is an effective way to dispose of industrial waste.