Evaluation of the mechanical behavior of concrete reinforced with waste tire steel fibers.

Concrete serves as the foundation of modern infrastructure and is commonly used in construction for its strength, durability, and versatility. However, traditional concrete has its limitations, especially when it comes to handling tensile stresses. To address this issue, different types of fiber reinforcement have been developed, with steel fiber proving to be particularly effective due to its high tensile strength and compatibility with concrete. This study investigated the effect of using waste tire steel fiber (WTSF) on the mechanical properties of concrete, where different percentages of WTSF were used namely, 0.25%, 0.5% and 1% by volume replacement of concrete. Compared to the control mix, the incorporation of steel fibers, whether commercially manufactured (MSF) or recycled (WTSF), negatively affected workability. Slump values in MSF mixes decreased between 37.5% and 62.5%, while WTSF mixes showed higher reductions, ranging from 87.5 to 100%, indicating that WTSF had a more adverse impact on workability. The compressive strength results showed that using WTSF at volume ratios of 0.25%, 0.5%, and 1% led to reductions of 6.4%, 30%, and 46%, respectively. In contrast, incorporating steel fiber enhanced mechanical performance, with tensile strength increasing by up to 67% for MSF and 38% for WTSF, while flexural strength improved by up to 40% and 19%, respectively.