Production and Characterization of a Composite Based on Plaster and Juncus Maritimus Plant Fibers

Nowadays, materials with a limited impact on the environment are required in the construction sector. Considering the interesting properties of natural elements such as natural fibers, it seems advantageous to use them to reinforce materials while protecting the environment and guaranteeing economic gain. Along these lines, this research was devoted to studying the effect of untreated natural fibers extracted from the Juncus maritimus plant (from Southern Morocco) on plaster. First, the effect of the percentage of added fibers on the fluidity of the plaster was evaluated by means of the Marsh's cone method, that is, by measuring the time taken by a known volume of plaster to flow from a cone through a short tube. Then, the highly porous microstructure of the plaster was observed using a scanning electron microscope (SEM). The diffractogram of Juncus maritimus fibers was built by means of a X-ray diffraction (XRD) method. The values obtained for the wet thermal conductivity of the composites decreased from 0.4853 W/m.K for the reference specimen to 0.4324 W/m K for a fiber volume content of 40%. The densities were calculated to determine the lightness of each composite. The mechanical strengths [flexural and compressive] were evaluated for different percentages of rush fibers. The addition of 20% volume fiber was found to improve the flexural strength to 3.63 MPa compared to the sample without fiber (3.36 MPa), thereby ensuring good toughness of the considered material. Nevertheless, a reduction in compressive strength was observed, due to the poor adhesion between the fibers and the plaster matrix.