A feasibility study of textile recycled fiber on the Fiber Reinforced Self-Compacting Concrete

Abstract

In this study, and feasibiltiy study of Fiber Reinforced Self-Compacting Concrete(FRSCC) using recycled fiber was conducted. To construct high-rise or complex buildings, concrete with fluidity and filling is needed while the materials used are not hardened. As a result, research on Self-Compacting Concrete(SCC) with high strength and high liquidity is needed. However, SCC has the disadvantage of being vulnerable to tensile and flexural strength and having a risk of cracking. To compensate for these shortcomings, research is actively carried out to compensate for the strength by using various fibers in SCCs. Unlike conventional FRSCC, the experiment was conducted using recycled fibers. The amount of waste fiber released recently is 100,000 tons per year and is increasing every year. Also, waste fiber can only be treated with incineration, which is not good for the environment. The types of fibers used in the experiment were nylon fiber, pet fiber and recycled fiber, and the dosage was made with 0%, 1% and 2%, and the characteristics of FRSCC were identified through slump test, air content test, U-Box test, compressive strength test, flexural strength test, chloride penetration test, carbonation test, and XRD analysis. The results of FRSCC's workability experiments show that the addition of fibers results in lower performance than the normal test specimen due to the adhesion between the fibers and the paste and the absorption of water in the fibers, but satisfies the JSCE SCC Grade 2 condition. The compressive strength test showed that the compressive strength of the recycled fiber was 10% lower than that of the Pet fiber, but it did not differ from the normal specimen and showed a value exceeding the design reference strength of 24MPa, and the flexural strength test result showed that the recycled fiber was 14% higher than normal specimen. The durability test results show that, when recycled fibers are used, the penetration depth of 13% and 23% lower than the normal test specimen can be identified in chloride penetration and carbonation tests. Finally, the XRD analysis confirmed that the addition of fiber does not have a significant effect on the hydration products of concrete. Experiments with three types of fibers showed that nylon fibers had the best performance. However, it is expected that recycled fibers will be worth studying through additional tests and textile coatings in the future as they also have similar performance as regular SCCs.