Saeid Fattahi

Short fiber–reinforced clay mortar is known as an important structural material in traditional and rural buildings because it not only provides superior mechanical properties but can also be easily produced by the rapid, low-cost molding process. The adhesion of the fibers to clay mortar has a significant role in the mechanical characteristics of fiber-reinforced mortar. In this study, interfacial shear stress (ISS) between nine different fibers and clay mortar was investigated by performing the Microbond test. Based on the findings, date palm fiber, hollow polyester, and polypropylene, respectively, demonstrated the highest degree of ISS with clay mortar; nevertheless, the lowest degree belonged to goat hair, acrylic, and wool, respectively. The critical lengths of the fibers to be embedded in the mortar as the short fiber reinforcements were calculated. The highest critical length belonged to glass fibers and date palm, respectively, and the lowest values belonged to acrylic, polyester, polypropylene, and wool, respectively.

In this study, we used an experimental design to investigate the influence of the total draft, break draft, distance between the aprons (Clips) and production roller pressure on yarn quality in order to obtain optimum drafting conditions for polyester and viscose (PES/CV) blend yarns in ring spinning frame. We used PES fibers (1.4 dtex × 38 mm long) and CV fibers (1.6 dtex × 38 mm long) to spin a 20 Tex blend yarn of PES (70%)/CV (30%) blend ratio. When the break draft, adjustment of distance between of aprons and roller pressure is not reasonable, controlling and leading of the fibers is not sufficient for proper orientation of the fibers in the yarn structure to produce a high quality yarn. Experimental results and statistical analysis show that the best yarn quality will be obtained under drafting conditions total draft of 38, 1.2 break draft, 2.8 mm distance between of aprons and maximum pressure of the production top roller (18daN).