Effect of fiber type on the mechanical properties and durability of hardened concrete

This paper studied the effects of basalt fibers (BF), polypropylene fibers (PF), end-hooked steel fibers (HSF), and wavy steel fibers (WSF) on the durability (impermeability and frost resistance) and mechanical properties (compressive, flexural, uniaxial tensile, and splitting tensile strength) of concrete based on the original mix proportion (water-binder ratio of 0.41). The results demonstrate that 0.5% of HSF has the best impact on enhancing concrete's compressive, flexural, and splitting tensile strength, with improvements of 10.88%, 21.02%, and 16.76%, compared to the control group. Meanwhile, 0.2% of BF has the best impact on improving the uniaxial tensile strength of concrete, with an improvement value of 18.91%. For concrete impermeability and frost resistance, 0.1% and 0.2% BF were the optimal fiber and content. However, PF was not very effective in improving the durability and mechanical property of concrete. Considering the scope of the investigated fiber content, the mechanical properties of concrete declined as fiber content rose. Still, the uniaxial and splitting tensile strengths improved as BF content rose. As the content of fiber in concrete increased, its impermeability weakened, and its ability to frost resistance improved. The above conclusions are highly significant for selecting fiber concrete types in future studies.

Automated summary

This paper studied the effects of different fibers on the durability and mechanical properties of concrete. The results showed that an appropriate amount of end-hooked steel fibers can effectively enhance the compressive, flexural, and splitting tensile strength of the concrete, while an appropriate amount of basalt fibers has the best improvement effect on the uniaxial tensile strength. Polypropylene fibers had a negligible effect on the durability and mechanical properties of the concrete. As the fiber content increased, the mechanical properties of the concrete declined but the uniaxial and splitting tensile strengths improved, impacting the impermeability and frost resistance of the concrete.