Ceramics-Silikáty 43, (3) 117 - 122 (1999)

The suitability of the mixture of by-pass cement dust as non plastic material and the clay for the production of bricks was tested. Three mixtures having the compositions 100/0, 90/10 and 80/20 (wt.%) clay - cement dust were investigated. Hand moulded briquettes were dried and fired for 2 hours at 600, 700, 900 and 1000 °C with firing rate 2.5 °C min⁻¹. The physical and mechanical properties of the dried and fired articles were measured. The results show that the substitution of 10 wt.% clay by cement dust increases the gas permeability of the fired bricks, which prevents bloating, and increases the crushing strength of bricks with firing temperature up to 1000 °C. The substitution of 20 wt.% cement dust brings the decrease in the crushing strength.