scholarly journals Investigation on the Influence of Type of Steel Fibers on Shear Failure of HPFRCC Beams

2018 ◽  
Vol 203 ◽  
pp. 06018
Author(s):  
Ehsan Nikbakht ◽  
Hugo Aureliano da Costa Gaspar ◽  
Rakan Mousa Jaradah ◽  
Muslich Hartadi Sutanto
Keyword(s):  
High Performance ◽  
Shear Failure ◽  
Steel Fiber ◽  
Load Capacity ◽  
Reinforcement Ratio ◽  
Beam Specimen ◽  
Shear Load ◽  
Longitudinal Reinforcement ◽  
Ultimate Load Capacity ◽  
High Performance Fiber

This paper investigates the influence of different types of steel fiber on the mechanical properties of High Performance Fiber Reinforced Cementitious Composite (HPFRCC) as well as the shear failure mode of steel reinforced HPFRCC beams. Moreover, the influence of parameters such as span to effective depths (a/d) ratio of beams and longitudinal reinforcement ratio on shear strength of HPFRCC beams are examined. In reference to the results, despite the same tensile strength of both straight and hooked fibers utilized, the performance of straight steel fiber is superior to the hooked steel fiber due to its physiognomies. However, the beam specimens with straight steel fiber exhibit considerably lower deflection and ultimate load capacity when subjected to shear load. Also, the results show that the influence of type of steel fiber is more significant than the influence of longitudinal reinforcement ratio, i.e. the beam specimen with hooked steel fiber and 0.94% reinforcement ratio displayed higher deflection and ultimate shear load capacity compared to the specimen with straight steel fiber and 1.88% longitudinal reinforcement ratio.

Reinforcement to Induce Ductile Behavior in an Ultra High Performance Fiber Reinforced Concrete Beam

2014 ◽  
Vol 629-630 ◽  
pp. 85-90
Author(s):  
Sang Mook Han ◽  
Xiang Guo Wu
Keyword(s):  
High Performance ◽  
Steel Fiber ◽  
High Performance Concrete ◽  
Small Diameter ◽  
Reinforced Concrete Beam ◽  
Fiber Reinforced Concrete ◽  
Production Costs ◽  
Longitudinal Reinforcement ◽  
High Performance Fiber ◽  
Ductile Behavior

The purpose of this study was to reduce production costs for UHPFRC members by using a bundle of longitudinal reinforcement bars as a substitute for steel fiber. Experiments on the ductile behavior of Ultra High Performance Concrete (UHPC) rectangular beams with a combination of steel fiber and longitudinal reinforcement bars were performed.The volume fractions of steel fiber were 0%, 0.7%, 1%, 1.5%, 2%, and the reinforcement ratios of longitudinal reinforcement bars that promoted ductile behavior were 0.0036, 0.016, 0.029 and 0.036.Fifteen UHPC beams were made with the combination of these test factors. Both the steel fiber and the longitudinal reinforcement bars had the effect of induciing ductile behavior for UHPC structural members. The load-deflection relationship, the concrete stress variation and the crack pattern indicated the usefulness of the bundle of longitudinal bars that have a small diameter with close arrangement.

scholarly journals Effects of Steel Fiber Percentage and Aspect Ratios on Fresh and Harden Properties of Ultra-High Performance Fiber

2021 ◽  
Vol 2 (3) ◽  
pp. 501-515
Author(s):  
Rajib Kumar Biswas ◽  
Farabi Bin Ahmed ◽  
Md. Ehsanul Haque ◽  
Afra Anam Provasha ◽  
Zahid Hasan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Aspect Ratio ◽  
High Performance ◽  
Steel Fiber ◽  
Setting Time ◽  
Fiber Reinforced Concrete ◽  
Future Research ◽  
Manufacturing Cost ◽  
Aspect Ratios ◽  
High Performance Fiber

Steel fibers and their aspect ratios are important parameters that have significant influence on the mechanical properties of ultrahigh-performance fiber-reinforced concrete (UHPFRC). Steel fiber dosage also significantly contributes to the initial manufacturing cost of UHPFRC. This study presents a comprehensive literature review of the effects of steel fiber percentages and aspect ratios on the setting time, workability, and mechanical properties of UHPFRC. It was evident that (1) an increase in steel fiber dosage and aspect ratio negatively impacted workability, owing to the interlocking between fibers; (2) compressive strength was positively influenced by the steel fiber dosage and aspect ratio; and (3) a faster loading rate significantly improved the mechanical properties. There were also some shortcomings in the measurement method for setting time. Lastly, this research highlights current issues for future research. The findings of the study are useful for practicing engineers to understand the distinctive characteristics of UHPFRC.

scholarly journals Experimental analysis of steel fiber reinforced concrete beams in shear

2022 ◽  
Vol 15 (3) ◽  
Author(s):  
Aaron Kadima Lukanu Lwa Nzambi ◽  
Dênio Ramam Carvalho de Oliveira ◽  
Marcus Vinicius dos Santos Monteiro ◽  
Luiz Felipe Albuquerque da Silva
Keyword(s):  
Shear Strength ◽  
Reinforced Concrete ◽  
Steel Fiber ◽  
Concrete Beams ◽  
Reinforcement Ratio ◽  
Steel Fibers ◽  
Reinforced Concrete Beams ◽  
Experimental Program ◽  
Longitudinal Reinforcement ◽  
Fiber Addition

Abstract Some normative recommendations are conservative in relation to the shear strength of reinforced concrete beams, not directly considering the longitudinal reinforcement rate. An experimental program containing 8 beams of (100 x 250) mm2 and a length of 1,200 mm was carried out. The concrete compression strength was 20 MPa with and without 1.00% of steel fiber addition, without stirrups and varying the longitudinal reinforcement ratio. Comparisons between experimental failure loads and main design codes estimates were assessed. The results showed that the increase of the longitudinal reinforcement ratio from 0.87% to 2.14% in beams without steel fiber led to an improvement of 59% in shear strength caused by the dowel effect, while the corresponding improvement was of only 22% in fibered concrete beams. A maximum gain of 109% in shear strength was observed with the addition of 1% of steel fibers comparing beams with the same longitudinal reinforcement ratio (1.2%). A significant amount of shear strength was provided by the inclusion of the steel fibers and allowed controlling the propagation of cracks by the effect of stress transfer bridges, transforming the brittle shear mechanism into a ductile flexural one. From this, it is clear the shear benefit of the steel fiber addition when associated to the longitudinal reinforcement and optimal values for this relationship would improve results.

scholarly journals Experimental Tests and Reliability Analysis of the Cracking Impact Resistance of UHPFRC

Fibers ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 74
Author(s):  
Hussain A. Jabir ◽  
Sallal R. Abid ◽  
Gunasekaran Murali ◽  
Sajjad H. Ali ◽  
Sergey Klyuev ◽  
...  
Keyword(s):  
High Performance ◽  
Steel Fiber ◽  
Impact Resistance ◽  
High Strength ◽  
Experimental Tests ◽  
Fiber Reinforced Concrete ◽  
Fiber Types ◽  
Impact Performance ◽  
High Performance Fiber ◽  
The Impact

Ultra-high performance (UHP) concrete is a special type of fibrous cementitious composite that is characterized by high strength and superior ductility, toughness, and durability. This research aimed to investigate the resistance of ultra-high performance fiber-reinforced concrete (UHPFRC) against repeated impacts. An adjusted repeated drop mass impact test was adopted to evaluate the impact performance of 72 UHPFRC disc specimens. The specimens were divided into six mixtures each of 12 discs. The only difference between the mixtures was the types of fibers used, while all other mixture components were the same. Three types of fibers were used: 6 mm micro-steel, 15 mm micro-steel, and polypropylene. All mixtures included 2.5% volumetric content of fibers, however with different combinations of the three fiber types. The test results showed that the mixtures with the 15 mm micro-steel fiber absorbed a higher number of impact blows until cracking compared to other mixtures. The mixture with pure 2.5% of 15 mm micro-steel fiber exhibited the highest impact resistance, with percentage increases over the other mixtures ranging from 25 to 140%. In addition, the Weibull distribution was used to investigate the cracking impact resistance of UHP at different levels of reliability.

scholarly journals Fire Resistance Investigation of Simple Supported RC Beams with Varying Reinforcement Configurations

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Yamin Song ◽  
Chuanguo Fu ◽  
Shuting Liang ◽  
Ankang Yin ◽  
Longji Dang
Keyword(s):  
High Temperature ◽  
Fire Resistance ◽  
Room Temperature ◽  
Shear Failure ◽  
Failure Time ◽  
Shear Capacity ◽  
Reinforcement Ratio ◽  
Longitudinal Reinforcement ◽  
Rc Beams ◽  
Vertical Deflection

To investigate fire-resistance behaviors of simple supported reinforced concrete (RC) beams with three faces exposed to fire, six full-scale specimens were designed in accordance with the principle of “strong bending and weak shearing.” One beam was treated as the control case of room temperature while the other five beams were exposed to high temperature. Parameters related to shear capacity were discussed, such as longitudinal reinforcement ratio and stirrup ratio. The experimental results show that brittle shear failure under room temperature may transfer to shear-bend failure at high temperature due to thermal expansion and strength degradation of concrete and steel. The greater the longitudinal reinforcement ratio, the longer the failure time of specimens. It indicates that the pinning action of longitudinal reinforcement can significantly improve the shear capacity of beams under high temperature. In addition, the configuration of stirrup reinforcement can effectively reduce the brittle change of vertical deflection when the beam enters the failure stage.

scholarly journals Numerical analysis of RC columns under cyclic uniaxial and biaxial lateral load

2021 ◽  
Vol 73 (10) ◽  
pp. 979-994
Keyword(s):  
Numerical Analysis ◽  
Lateral Displacement ◽  
Reinforcement Ratio ◽  
Shear Load ◽  
Longitudinal Reinforcement ◽  
Initial Stiffness ◽  
Structural Behaviour ◽  
Cross Sectional ◽  
Rc Columns ◽  
Cyclic Shear

A numerical finite element study is conducted in this paper to examine structural behaviour of high strength RC columns exposed to biaxial and uniaxial lateral displacement histories with constant axial load. The numerical analysis of 24 models was made using ABAQUS / CAE. The comparison between numerical analysis and experimental results shows good agreement through validations. The considered parametric study involves determination of the longitudinal reinforcement ratio, total cross-sectional area of confinement steel (Ash), and uniaxial and biaxial cyclic shear load. Numerical analysis results show that an increase of longitudinal reinforcement for a uniaxial and biaxial lateral historic load will significantly increase maximum and ultimate load of columns, corresponding deflections, number of cycles at maximum and ultimate loads, and initial stiffness Ki, while the effect of transverse reinforcement is less pronounced. The columns load and deformation capacity decreases significantly with application of biaxial cyclic shear load, compared with uniaxial load. Also, this effect reduces with an increase in longitudinal reinforcement ratio (%ρl) and Ash.

Sign in / Sign up

Export Citation Format

Share Document