Volcanic Tuff as Secondary Raw Material in the Production of Clay Bricks
Nicoleta Cobîrzan,
Gyorgy Thalmaier,
Anca-Andreea Balog,
Horia Constantinescu,
Andrei Ceclan,
Mircea Nasui
Affiliations
Nicoleta Cobîrzan
Department of Civil Engineering and Management, Faculty of Civil Engineering, Technical University of Cluj-Napoca, 25 Baritiu Street, 400624 Cluj-Napoca, Romania
Gyorgy Thalmaier
Department of Materials Science and Engineering, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103 Muncii blv., 400624 Cluj-Napoca, Romania
Anca-Andreea Balog
Department of Structures, Faculty of Civil Engineering, Technical University of Cluj-Napoca, 25 Baritiu Street, 400624 Cluj-Napoca, Romania
Horia Constantinescu
Department of Structures, Faculty of Civil Engineering, Technical University of Cluj-Napoca, 25 Baritiu Street, 400624 Cluj-Napoca, Romania
Andrei Ceclan
Department of Electronics and Measurements, Faculty of Electrical Engineering, Technical University of Cluj-Napoca, 26 Baritiu Street, 400624 Cluj-Napoca, Romania
Mircea Nasui
Department of Physics and Chemistry, Faculty of Materials and Environmental Engineering, Technical University of Cluj-Napoca, 103 Muncii blv., 400624 Cluj-Napoca, Romania
The present work examines an innovative manufacturing technique for fired clay bricks, using tuff as a secondary raw material. Samples were made of clay and tuff (0–30 wt.%) fired at 900 to 1100 °C. The chemical and mineralogical compositions and physical and thermal analyses of raw materials were investigated by using SEM-EDS, RX and DTA-TG curves. The samples were analysed from the mineralogical, technological and mechanical points of view. The result show that the tuff’s presence in the clay mixtures considerably reduced the shrinkage of the product during the firing process, and the manufactured samples were of excellent quality. The compressive strength of the bricks varied from 5–35.3MPa, being influenced by the tuff content, clay matrix properties and firing temperatures. Finally, the heat demand for increasing the temperature from room to the firing temperature of the sample with 10% tuff content was 22%.
