Experimental Study on Bond Behavior between Steel Rebar and PVA Fiber-Reinforced Concrete

Abstract

An experimental test was performed to study the bond behavior between steel rebar and concrete reinforced by polyvinyl alcohol (PVA) fibers. Twenty specimens were prepared and subjected to the pull-out test. Four different fiber volume contents (0%, 0.2%, 0.4%, and 0.6%) were considered and the concrete with the strength grade of C35 was designed in the present study. The effects of PVA fibers, rebar diameter, and cover depth on bond behavior were clarified. The effects of PVA fibers on the mechanical property of concrete were also studied. The results show that PVA fibers decreased the compressive strength of concrete, but increased splitting tensile, flexural, and direct tensile strength. PVA fibers negatively affected bonding in the ascending branch both for the pull-out and the splitting failure cases, but improved the bonding in the descending branch after peak stress for the splitting failure case. In the present test, the maximum decrement of bond strength was about 16.2% for specimens with less than 0.6% PVA fibers. PVA fibers restricted both the macro-cracking and micro-cracking for the splitting cases, the former were much more significant than the latter. The effects of rebar diameter and cover depth on bonding became slight and significant with the increasing content of PVA fibers, respectively.

Experimental investigations of the bond strength between iron tailing concrete and steel bars

“…Comparing the ITPC and CC, although the compressive strength of ITPC was similar to that of the CC, the splitting tensile strength of the former was lower than that of the latter, and the ultimate bond stress was positively correlated with the splitting tensile strength of the concrete, [28][29][30][31] implying that the ultimate bond stress of the ITPC specimen was lower than that of the CC specimen.…”

“…23 In recent years, a considerable amount of research on the bond performance of concrete and rebars has been conducted on coral-reef-sand concrete, recycled aggregate concrete, high-strength concrete, reactive powder concrete, steel fiber highstrength ceramsite concrete, retard-bonded prestressed concrete, and concrete under high temperature conditions. [23][24][25][26][27][28][29][30][31][32] In addition to the type of concrete, various other factors can affect the bond performance between concrete and rebars and have been extensively studied, 33,34 such as the anchorage length, resistance to splitting crack development provided by the concrete cover, 34,35 bar diameter, 36 rib geometry, 37 rebar corrosion and cracking widths, 38 interfacial fracture energy at the rebar-concrete interface, 39 confinement provided by transverse reinforcement, 40 and transverse compression and casting positions of concrete members. 41 The question of how the bond performance is affected by different types of iron tailing concrete (ITC) is an important basis for the application of ITC in engineering.…”

Mechanical Properties of Cement Mortars Reinforced with Polypropylene Fibers Subjected to High Temperatures and Different Cooling Regimes

“…In construction, steel and PP fibers are commonly employed, although recently there have been investigations on the inclusion of polyvinyl alcohol fibers [20,21]. The addition of steel fibers in concrete is the most employed method, which improves the mechanical behavior of concrete.…”

“…Polyvinyl alcohol (PVA) fibers have high strength and ductility, in addition to excellent corrosion resistance without toxicity, improving the subsequent behavior of concrete after cracking and increasing its ductility and toughness. However, the incorporation of PVA fibers produces a significant decrease in the fluidity of concrete mixtures, generating higher porosity and affecting the matrix [20,21].…”