Title:
Split Tensile Behavior of Recycled Steel Fiber-Reinforced Concrete
Author(s):
T. Asheghi Mehmandari, M. Shokouhian, M. Imani, K. F. Tee, and A. Fahimifar
Publication:
Materials Journal
Volume:
122
Issue:
2
Appears on pages(s):
15-28
Keywords:
digital image correlation (DIC); fiber interface transition zone (FITZ); recycled steel fibers (RSFs); scanning electron microscopy (SEM); split tensile behavior; sustainable fiber-reinforced concrete (FRC)
DOI:
10.14359/51744375
Date:
3/1/2025
Abstract:
This study investigates the behavior of recycled steel fibers (RSFs)
recovered from waste tires and industrial hooked-end steel fibers
(ISF) in two single and hybrid reinforcement types with different
volume content, incorporating microstructural and macrostructural
analyses. Scanning electron microscopy (SEM) is used to
study the microstructure and fractures, focusing on crack initiation
in the fiber interface transition zone (FITZ). The macrostructural
analysis involves using digital image correlation (DIC) software,
Ncorr, to analyze the split tensile behavior of plain and fiber reinforced concrete (FRC) specimens, calculating strain distribution and investigating crack initiation and propagation. The
SEM study reveals that, due to the presence of hooked ends, industrial fibers promoted improved mechanical interlocking; created anchors within the matrix; added frictional resistance during crack propagation; significantly improved load transfer; and had better bonding, crack bridging, and crack deflection than recycled fibers. RSFs significantly delay crack initiation and enhance strength in the pre-peak zone. The study suggests hybridizing recycled fibers
from automobile tires with industrial fibers as an optimum strategy
for improving tensile performance and using environmentally
friendly materials in FRC.