Effect of Recycled-Steel Fibers on Compressive Strength and Shrinkage Behavior of Self-Compacting Concrete

the employment of steel fibers extracted from scrap tires in the production of fiber reinforced self-compacting concrete (SCC) is a new challenge in reducing the impact of these waste materials on the environment. This study aims to assess the effect of Recycled Steel Fibers (RSF) on compressive strength and shrinkage behavior of SCC by including different fibers length in addition to use hybrid contents. Eight mixes of recycled steel fibers self-compacting concrete (RSFSCC) were produced. The control mix, single RSF length content mixes and hybrid content mixes (replacement of short fibers by long fibers at contents of 30%, 50% and 70%) were prepared. The total RSF content was kept constant at 60 kg/m3. The results show that the addition of RSF affects the free shrinkage of SCC mixes particularly after 28 days of drying. The addition of RSF delays the cracking time in addition to reduce the width of cracks. None of SCC mixes exhibited cracking when using hybrid (long and short) RSF was used.