Formulation and Thermomechanical Characterization of Earth-based Biosourced Composites: Cases of Clay-Hibiscus cannabinus L. Fiber, Clay-sawdust and Clay- Oryza sativa Husk

This work concerns the technical study of implementation, thermal and mechanical characterization of a composite material based on clay and plant fibers, in order to meet the need for bioclimatic and sustainable houses. The objective was to find the proportions of clay and fibers to obtain a mixture that would give better thermal properties. A characterization of the thermal properties was made thanks to the KD2 Pro analyzer on samples of various formulas of mixture clay-plant fibers. The results obtained showed that the thermal properties such as thermal conductivity and thermal diffusivity of the clay-fiber mixture samples decrease with the increase of the fiber content in the mixture. Thus, the thermal conductivity of the samples varies from 0.85 to 0.65 W/m.K; from 0.88 to 0.72 W/m.K and from 0.83 to 0.75 W/m.K respectively with Hibiscus cannabinus L. fiber, sawdust and Oryza sativa husk. As for the thermal diffusivity, it varies from 0.37 to 0.25 mm2/s; from 0.45 to 0.30 mm2/s and from 0.47 to 0.27 mm2/s respectively with the addition of Hibiscus cannabinus L. fibers, sawdust and Oryza sativa husk. In sum, the earth samples stabilized with Hibiscus cannabinus L. fibers offer better thermal properties for the construction of bioclimatic houses.