Laboratory-testing and industrial scale performance of different clays from eastern Morocco for brick manufacturing

This study aims to the valorization of soil materials (unfired and fired) for sustainable buildings in eastern Morocco. To make this study more representative, four clay soils from different areas were considered in this investigation (i.e., Zaio, Oujda, Lota, and Midar). Geotechnical tests revealed that all samples exhibit a high clay content and medium plasticity. X-ray diffraction, thermal gravimetric analysis and energy dispersive X-ray spectroscopy of the soils showed the presence of quartz, calcite and several clay minerals. The significant clay content and the high density of the bricks (1589-1713 kg.m- 3) have an effect on the properties of the unfired solid clay brick. Experimental results have shown that the thermal conductivity and compressive strength of the unfired solid clay brick vary between (0.77-1.07 W.m- 1K-1) and (1.7-2.4 MPa) respectively. The cavities and firing process for fired hollow clay bricks contributed to the increase in thermal and mechanical resistance of the bricks by (0.19-0.4 W.m- 1K-1) and (2.9-5 MPa) respectively. After identification of all the samples, the authors' justified choice was to use the soil collected from the Lota site for the ANSYS-Fluent hybrid wall case studies. In comparison to the other cases, the configuration (Mortar/Fired hollow clay brick and unfired solid clay brick/ Mortar) demonstrated a 2 h improvement in time lag and a considerable decrease in the amplitude of the temperature fluctuation. Therefore, unfired solid clay bricks and fired hollow clay bricks may be used in com-bination to provide thermal comfort for a sustainable building.

Automated summary

This study investigates the use of unfired and fired soil materials for sustainable buildings in eastern Morocco. Geotechnical tests and analysis revealed high clay content and medium plasticity in the soil samples. The thermal conductivity and compressive strength of the unfired solid clay brick were found to vary between 0.77-1.07 W.m-1K-1 and 1.7-2.4 MPa respectively. The firing process of the hollow clay bricks significantly increased thermal and mechanical resistance. The study suggests that a combination of unfired solid clay bricks and fired hollow clay bricks can provide thermal comfort for sustainable buildings.