Effects of hemp fibers on characteristics of cement based mortar

In recent years, using addition of fibers with plant origin in concretes has increased significantly. They not only enhance the mechanical characteristics of cement mortars, but also they are renewable, easy to access and cheap and this makes the use of plant fibers more widespread. Hemp fiber is a plant, which is planted in many places of the world and obtained in large amounts, is environmentally friendly and also used in manufacturing of composite materials. In this study, hemp fiber reinforced cement mortars with different ratios (0%, 1%, 2%, 3%) and different lengths (6 mm, 12 mm and 18 mm) were manufactured. Density, water absorption, compressive strength, flexural strength, compressive strength after flexural tensile and splitting tensile strength tests were performed on manufactured samples. Also, in order to determine the inner structural characteristics of samples, SEM analysis was conducted. As a result of the study, it was determined that cement mortars reinforced with 2–3% amount and 12 mm length of natural hemp fiber give the optimum results.