Interfacial bond characteristics of steel fibers embedded in cementitious composites at high rates

The dynamic material properties of high performance hybrid fiber reinforced cementitious composites (HFRCC) with various volumetric fractions of steel and polyvinyl alcohol (PVA) fibers were studied by the Split Hopkinson Press Bar (SHPB) test. The results show that HFRCC with higher volumetric fraction of steel fibers are more sensitive to stain rate and the dynamic compressive strength increase more prominently with the strain rate increasing, but peak strain shows the opposite trend. The PVA fibers increase the ductility of HFRCC more effectively than steel fibers. Compared to PVA fiber reinforced cementitious composites (FRCC), HFRCC present better dynamic material properties under impact loading.

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Bond Characteristics between ECC (Engineered Cementitious Composites) and GFRP Rebars

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.1010 ◽

2012 ◽

Vol 602-604 ◽

pp. 1010-1013

Author(s):

Yun Cheol Choi

Keyword(s):

Fiber Reinforced Concrete ◽

Fiber Reinforced Polymers ◽

Cementitious Composites ◽

Fiber Reinforced ◽

Engineered Cementitious Composites ◽

Bond Slip ◽

Glass Fiber Reinforced ◽

Concrete Type ◽

Gfrp Rebars ◽

Bond Characteristics

The purpose of this study is to investigate the bond characteristics between ECC(Engineered Cementitious Composites) and GFRP(Glass Fiber Reinforced Polymers) rebars. An experimental study was carried out to investigate the bond-slip properties of the steel and GFRP rebars in ECC which was reinforced with Polyvinyl Alcohol(PVA) fibers. A total of 8 beam specimens, which was designed according to the RILEM guidelines, was tested according to the RILEM guideline. The main objective was evaluating the load versus displacement and load versus slip behavior and the bond strength regarding the influence of the following parameters : concrete type(Normal concrete and fiber reinforced concrete) and bar diameter and type. From the test results, concrete and ECC specimen presented similar behavior for steel reinforced specimen. However, GFRPO reinforced specimen show different behavior with that. Comparative study for test and equations of MC90 was carried out and code provision predicted the bond characteristics conservatively.

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Width effect of interfacial bond characteristics

Construction and Building Materials ◽

10.1016/j.conbuildmat.2019.06.106 ◽

2019 ◽

Vol 220 ◽

pp. 712-726 ◽

Cited By ~ 5

Author(s):

Yu-Fei Wu ◽

Liang He

Keyword(s):

Interfacial Bond ◽

Width Effect ◽

Bond Characteristics

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Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

Open Engineering ◽

10.2478/s13531-012-0015-3 ◽

2012 ◽

Vol 2 (3) ◽

Cited By ~ 2

Author(s):

Farhad Aslani ◽

Shami Nejadi

Keyword(s):

Steel Fiber ◽

Steel Reinforcement ◽

Steel Fibers ◽

Fiber Types ◽

Reinforcing Steel ◽

Structural Elements ◽

Fiber Reinforced ◽

Self Compacting Concrete ◽

Inclined Angle ◽

Bond Characteristics

AbstractSteel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths (τ (app)) and slip coefficient (β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle (ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers, information is hardly available in this area. In this study, bond characteristics of deformed reinforcing steel bars embedded in SFRSCC is investigated secondly.

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Deformation and Compressive Strength of Steel Fiber Reinforced MgO Concrete

Materials ◽

10.3390/ma12213617 ◽

2019 ◽

Vol 12 (21) ◽

pp. 3617 ◽

Cited By ~ 6

Author(s):

Feifei Jiang ◽

Zhongyang Mao ◽

Min Deng ◽

Dawang Li

Keyword(s):

Compressive Strength ◽

Steel Fiber ◽

Steel Fibers ◽

Fiber Reinforced ◽

Interfacial Bond ◽

Interfacial Bond Strength ◽

Ordinary Concrete ◽

Brittle Behavior ◽

Compressive Strength Of Concrete ◽

Mgo Concrete

To reduce the cracking caused by shrinkage and avoid the brittle behavior of concrete, MgO expansion agent and steel fibers were used in this paper. Firstly, the effect of MgO and steel fibers on the compressive strength of concrete was compared. The results showed that the compressive strength of steel fibers reinforced concrete (SC) and steel fiber reinforced MgO concrete (SMC) was significantly improved. Compared with ordinary concrete (OC), SMC’s 28 days compressive strength increased by 19.8%. Secondly, the influence of MgO and steel fibers with different contents on the self-volumetric deformation of concrete was compared through the experiment. The results showed that as a result of the hydration expansion of MgO, MC and SMC both showed obvious expansion, and their 190 days expansion was 335 μ ε and 288 μ ε , respectively. Lastly, through a scanning electron microscope (SEM) test, it was found that the constraint effect of steel fibers changed the expansion mode of MgO from outward expansion to inward extrusion, thus improving the interfacial bond strength of concrete.

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