Properties of Fired Clay Bricks Mixed with Waste Glass

This study is to investigate the effect of adding waste glass on the properties of fired clay bricks. Two different particle sizes (smaller than 150 μm and 600 μm ) of waste glass are added to clay mixes at contents of 0, 10, 20, 30 and 40% per weight. Brick samples are fired at 900, 1000 and 1100°C in an electrical furnace for 6 hours, at a heating rate of 5°C/min. The physical and mechanical properties of fired clay bricks are studied. The firing shrinkage, bulk density and compressive strength of the bricks increase as the amount of waste glass content increases and as firing temperature increases. The apparent porosity and water absorption decrease with the increase of the amount of waste glass and firing temperature. The particle size of waste glass powder was very important and had a significant effect on the properties of fired clay bricks; the finer the particle size, the higher the compressive strength. Based on the executed testing program, it is found that the optimal properties of fired bricks are achieved at 30% content of waste glass and a firing temperature of 1100°C. The results also prove that it is possible to make bricks with compressive strength in excess of 95 MPa and water absorption not more than 6%.