Improvement of Tozeur’s fired bricks properties: an experimental approach

This study aims to produce more sustainable, resilient, and well-fashioned built materials having enhanced physical, mechanical, and thermal properties using raw material extracted from the area near Tozeur town, located in the southwestern Tunisia. In the performed experiments, various raw materials (greenish clay (CL₁) and reddish clay (CL₂) are mixed in different proportion to obtain three different mixtures: M₁, M₂, and M₃. To analyze the composition of clays mixture, mineralogy and chemical composition tests have been conducted. Better humidification and optimum moisture were used for the clay mixtures to obtain flexible and smooth clay dough. Then the different clays doughs obtained were molded to form different brick samples. Some of these samples were dried at ambient temperature, while the others were fired at 400 °C, 600 °C, 800 °C, and 1000 °C for 24 h. Thermogravimetry, compressive, and flexural strength of the obtained bricks were examined to show how their characteristics were affected by the firing temperature. The experimental results revealed that the sample made up of M₁ ( \({\raise0.7ex\hbox{$1$} \!\mathord{\left/ {\vphantom {1 3}}\right.\kern-0pt} \!\lower0.7ex\hbox{$3$}}CL_{1}\) $1\left./\phantom{13}\right)3C{L}_1$ and \({\raise0.7ex\hbox{$2$} \!\mathord{\left/ {\vphantom {2 3}}\right.\kern-0pt} \!\lower0.7ex\hbox{$3$}} \, CL_{2}\) $2\left./\phantom{23}\right)3C{L}_2$ ), fired at 600 °C, has the best properties as its compressive strength increased by 310% and its flexural strength was enhanced by 47.7%. We also obtained a beautifully finished product. In addition, we observed that a large quantity of energy can be economized and can contribute to rescuing nature from pollution.