Evaluation of the tensile strength of waste tire textile fibers reinforced shotcrete (case study of Baghan-Marivan tunnel, Kurdistan Province)

Today, shotcrete as a support system is widely applied in various surface and underground structures. Hence, in recent years, numerous studies have been conducted to improve the quality of shotcrete including the strength and ductility. Investigating the impact of adding different fibers to shotcrete is one of the most important research done in the field of shotcrete development. In the present research, the effect of using waste tire textile fibers on the tensile strength of shotcrete has been investigated by field implementation. For this purpose, the operation of shotcreting containing 0.5, 1, and 1.5% of waste tire textile fibers along with fiber-free panels was performed at the Baghan-Marivan tunnel project site. After preparing the required samples, the Brazilian tensile strength test was performed. The results demonstrated that waste tire textile fiber causes a significant increase in the energy absorption capacity of shotcrete and eliminate its brittle behavior. Other advantages of waste tire textile fibers include reduction of rebound, easy pumping, low weight, as well as high durability of fibers in acidic and wet environments. Forthermore, since this fiber is recycled, its utilizing in shotcrete industary, in addition to reducing the environmental problems, will lead to a significant reduction in the cost of the project.