Developing Sustainable Building Materials Using Local Soil Reinforced with Alkali-Treated and Untreated Alfa Fiber: A Characterization Study of Thermal and Mechanical Properties

This study aimed to investigate the effect of Alfa fiber on the thermal conductivity and compressive strength of soil of the region of Marrakech ( Morocco). Raw and treated Alfa fibers were added to the soil in concentrations ranging from 0 to 4% to assess mechanical and thermal properties. This work also included mineralogical, chemical, and physical characterization of raw materials (soil and fiber) to provide a comprehensive understanding of the relationship between fiber and soil properties. The results showed that both compressive strength and thermal conductivity of the soil decreased as the fiber content increased. The thermal conductivity of the treated fibers was found to be higher than that of the raw fibers. The compressive strength was found to be lower for the untreated Alfa fiber compared to the treated one with 1 mol/l of NaOH. The results of this study also showed that the compressive strength decreased with increasing fiber length, suggesting that longer fibers may have a negative effect on the mechanical properties of the reinforced soil. On the other hand, the addition of cement to the soil mix resulted in a significant improvement in the compressive strength of the soil. The optimal combination of parameters for improved compressive strength was achieved by using treated Alfa fiber with a fiber length of 1-and 9% cement content.