Experimental Study of the Reinforcement of Unstabilized and Stabilized Local Clay Materials with Date Palm Fibers

Abstract. The aim of this study is to experimentally test the stabilization of unexploited clay from the Errachidia region (south-east Morocco) with date palm spathes, with a view to its potential use in construction. The main objective of the present work is to evaluate the thermophysical and mechanical behavior of fiber-stabilized clay blocks. Several samples of spathe-reinforced clay at six different grades (0%, 1%, 2%, 3%, 4%, and 5%) were prepared and tested. Thermal characterization was carried out using the PHYWE House thermal insulation method to determine thermal conductivity and resistance. Mechanical performance was measured in terms of compressive and flexural strength. In addition, the chemical identification of Errachidia clay was studied using the X-ray fluorescence method. The results of the clay identification showed that Errachidia clay meets the minimum requirements for the manufacture of compressed earth bricks and adobe. The results of the thermophysical tests showed that the addition of date palm spathes had a positive influence on the lightness and thermophysical properties of the clay samples stabilized by the spathes. In terms of mechanical test results, the flexural and compressive strengths of clay blocks stabilized with date palm fibers continue to increase up to a fiber content of 3%. After this content, mechanical performance decreases with the addition of spathes and no improvement is detected. Consequently, a fiber content of 3% represents the optimum content for stabilizing Errachidia clay. At this content, stabilized clay blocks show optimal mechanical performance and improved thermal properties compared to reference samples. However, increasing the percentage of fiber mass leads to an increase in water absorption and a decrease in density. Clay compounds reinforced with date palm spathe can be considered as environmentally friendly building materials.