Experimental and Numerical Investigation on Stress-Strain Relationships of GFRP and Lateral Ties Confined Polyolefin Fibre Reinforced Concrete under Monotonic Axial Compression

2012 ◽  
Vol 253-255 ◽  
pp. 466-473 ◽  
Author(s):  
S. Palanivel ◽  
M. Sekar
Keyword(s):  
Reinforced Concrete ◽  
Volume Fraction ◽  
Secondary Reinforcement ◽  
Fiber Reinforced Concrete ◽  
Seismic Resistance ◽  
Behavioral Differences ◽  
Synthetic Fibers ◽  
Reinforced Polymer ◽  
Fibre Reinforced Polymer ◽  
Low Modulus

In this investigation, the combined confinement effect of spacing of lateral ties, volume fraction of polyolefin fibres and fibre reinforced polymer(FRP) wraps was studied both experimentally and analytically from the point of deformability characteristics of concrete for seismic resistance. Low modulus synthetic fibers such as polyolefin based fibers, it is shown that polyolefin fibers with sufficient tensile strength can successfully enhance the mechanical properties of concrete. The mechanism of delaying and arresting the progressive internal cracking by the fibres can be made use in passive confinement of concrete. In this study the confinement effectiveness of GFRP wraps of single and double layer and polyolefin fibres of volume fractions 0.7% and 0.9% in addition to lateral ties of spacing 145mm and 75mm on concrete prisms of size 150 ×150 ×300 mm were investigated. Such concrete is termed as FRP confined fiber reinforced concrete(FRPCFRC).This paper presents an analytical model(profile) for predicting the constitutive behaviour of FRPCFRC based on the experimental and analytical results. A total of thirty nine prisms of size 150 ×150 ×300 mm were cast and tested under strain control rate of loading. The results of the testing demonstrate the behavioral differences between FRP confined concrete and FRP confined FRC and the ability of the synthetic macro fiber to be used as secondary reinforcement in performance based seismic resistance applications.

Constitutive Behaviour of Lateral Ties Confined Polyolefin Fibre Reinforced Concrete under Monotonic Axial Compression

2012 ◽  
Vol 253-255 ◽  
pp. 367-375 ◽  
Author(s):  
S. Palanivel ◽  
M. Sekar
Keyword(s):  
Reinforced Concrete ◽  
Volume Fraction ◽  
Secondary Reinforcement ◽  
Fiber Reinforced Concrete ◽  
Constitutive Behaviour ◽  
Fiber Reinforced ◽  
Behavioral Differences ◽  
Synthetic Fibers ◽  
The Matrix ◽  
Low Modulus

In this investigation, the combined effect of spacing of lateral ties and volume fraction of polyolefin fibres was studied both experimentally and analytically from the point of deformability characteristics of concrete. Low modulus synthetic fibers such as polyolefin based fibers, it is shown that polyolefin fibers with sufficient tensile strength can successfully enhance the mechanical properties of concrete. The mechanism of delaying and arresting the progressive internal cracking from transition zone to the matrix by the fibres can be made use in passive confinement of concrete. Such concrete was termed as polyolefin fiber reinforced concrete (PFRC). In this study the confinement effectiveness of polyolefin fibres of volume fractions 0.3%,0.5%,0.7%,0.9% and 1.2% in addition to lateral ties of spacing 290mm, 145mm and 75mm on concrete prisms of size 150 ×150 ×300 mm were investigated. Such concrete is termed as confined polyolefin fiber reinforced concrete (CPFRC).This paper presents an analytical model(profile) for predicting the constitutive behaviour of CPFRC based on the experimental and analytical results. A total of seventy two prisms of size 150 ×150 ×300 mm were cast and tested under strain control rate of loading. The increase in strength and strain of CPFRC were used in formulating the constitutive relation. The results of the testing demonstrate the behavioral differences between plain and CPFRC and the ability of the synthetic macro fiber to be used as secondary reinforcement in seismic resistance applications.

scholarly journals Synergetic Effect of Sugarcane Bagasse Ash with Low Modulus of Fiber Reinforced Concrete

2019 ◽  
Vol 8 (3) ◽  
pp. 7171-7175
Keyword(s):  
Reinforced Concrete ◽  
High Performance ◽  
High Performance Concrete ◽  
Volume Fraction ◽  
Research Work ◽  
Synergetic Effect ◽  
Plain Concrete ◽  
Fiber Reinforced Concrete ◽  
Low Modulus ◽  
Sugar Cane Bagasse Ash

This research work has experimentally investigated on the effects of low modulus fibers (PP) used in concrete for the various percentages like 0. 0.5% and 1.0% (by volume fraction) along with different percentage of sugar cane bagasse ash from 0 to 15% replaced in Portland cement (by weight of binding material) for different mixes and tested for the various properties of high-performance concrete (HPC). This experimental test results indicated that the usage of SCBA is restricted up to 10% with 0.5% of PP (Polypropylene) along with 1.5% of superplasticizers produces the higher flexural strength was increased up to 78.30% and compressive strength of concrete was increased up to 25.80% when compared to control (plain) concrete at 28 days. Finally, the usage of low modulus fibre reinforced concrete to act as a corrosion inhibitor agent during the chloride attack than compared to high modulus fibers and reduce the plastic shrinkage due to excellent flexibility in concrete and also increases the life span.

scholarly journals Exploration of Characteristics of Steel Fiber Reinforced Concrete and Its Influence on Regular Concrete

2020 ◽  
Vol 9 (2) ◽  
pp. 209-212
Keyword(s):  
Reinforced Concrete ◽  
Steel Fiber ◽  
Volume Fraction ◽  
Natural Fibers ◽  
Plain Concrete ◽  
Fiber Content ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Synthetic Fibers

Concrete is the most widely used product in the construction sector mainly because of its properties and its capability to be moulded to any size. Plain concrete has low tensile strength and forms internal micro cracks. It has been proven that with the addition of natural fibers and synthetic fibers in concrete, it helps in the durability and functionality of structure. The steel fibers are added to the concrete in very low volume doses and it has been effective in decreasing the plastic shrinkage in cracking and also acting as a crack arrestor. In this journal, experimental analysis on steel fiber reinforced concrete is done on M30 and M50 mix with 0.5%, 1%, 1.5% and 2% volume fraction of steel fiber content and is compared with samples of 0% steel fiber content and these samples are investigated on their compressive, split tensile and flexural strengths.

EVALUATION OF COMPRESSIVE STRENGTH OF SYNTHETIC FIBER REINFORCED CONCRETE

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Saman Hedjazi ◽  
Daniel Castillo
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Reinforced Concrete ◽  
Fiber Volume Fraction ◽  
Volume Fraction ◽  
Fiber Reinforced Concrete ◽  
Synthetic Fiber ◽  
Fiber Reinforced ◽  
Fiber Volume ◽  
Synthetic Fibers

This paper evaluates the effect of discrete fibers in concrete on the pulse velocity and mechanical properties of FRC. Two different type of synthetic fibers consisting of Polypropylene and Nylon were investigated. The effect of concrete mix proportions such as types of fiber, volume fraction of fiber, water-to-cement ratio (w/c), and curing conditions were examined. An experimental program was designed and conducted on 100 mm x 200 mm cylindrical specimens to evaluate the properties of FRC. The compressive strength obtained from the Compression Test Machine (CTM) was compared to those calculated from UPV. The difference between two types of synthetic fibers on concrete properties were investigated. Results show that the highest compressive strength of Polypropylene Fiber Reinforced Concrete (PFRC) was achieved at 0.5% fiber volume fraction, whereas for Nylon Fiber Reinforced Concrete (NFRC) the highest compressive strength was obtained at 1.0% fiber volume fraction. Additionally, results show that the available equations relating UPV to compressive strength of concrete need modifications when used for different fibers. Therefore, either new or modified empirical equations are needed for better estimation of mechanical properties of FRC.

Behaviour of reinforced GFRP bars concrete beams having strengthened splices using CFRP sheets

2021 ◽  
pp. 136943322110015
Author(s):  
Akram S. Mahmoud ◽  
Ziadoon M. Ali
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beams ◽  
Reinforced Concrete Beams ◽  
New Method ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Strength Capacity ◽  
Cfrp Sheet ◽  
Carbon Fibre Reinforced Polymer ◽  
Fibre Reinforced Polymer

When glass fibre-reinforced polymer (GFRP) bar splices are used in reinforced concrete sections, they affect the structural performance in two different ways: through the stress concentration in the section, and through the configuration of the GFRP–concrete bond. This study experimentally investigated a new method for increasing the bond strength of a GFRP lap (two GFRP bars connected together) using a carbon fibre-reinforced polymer (CFRP) sheet coated in epoxy resin. A new splicing method was investigated to quantify the effect of the bar surface bond on the development length, with reinforced concrete beams cast with laps in the concrete reinforcing bars at a known bending span length. Specimens were tested in four-point flexure tests to assess the strength capacity and failure mode. The results were summarised and compared within a standard lap made according to the ACI 318 specifications. The new method for splicing was more efficient for GFRP splice laps than the standard lap method. It could also be used for head-to-head reinforcement bar splices with the appropriate CFRP lapping sheets.

Static Behavior of Layered Fiber Reinforced Concrete T-Shaped Beam

2010 ◽  
Vol 168-170 ◽  
pp. 2037-2043
Author(s):  
Yin Gu ◽  
Wei Dong Zhuo ◽  
Yu Ting Qiu
Keyword(s):  
Reinforced Concrete ◽  
Volume Fraction ◽  
Fiber Reinforced Concrete ◽  
Parameter Analysis ◽  
Beam Specimen ◽  
Rc Beam ◽  
High Modulus ◽  
Fiber Reinforced ◽  
Initial Stiffness ◽  
Fiber Volume

This paper proposes a concept of layered fiber reinforced concrete (LFRC) beam. In the concept of a LFRC beam, low-modulus fiber and high-modulus fiber are randomly dispersed and uniformly distributed into the concrete matries of the compression and tension zones, respectively. The static behaviors of LFRC beam are investigated from both experimental and numerical aspects. Four-point bending tests are performed on two simply supported T-shaped LFRC beam specimens and an ordinary T-shaped RC beam specimen with large scales. Comparison between the testing results of LFRC and RC beam specimens shows that the initial cracking load, flexural toughness and post-yielding stiffness of a LFRC beam can be significantly improved, but the ultimate loads are nearly without change. Numerical simulations are also carried out to investigate the static behaviors of the LFRC beam specimens. It is found that the simulation results are agreed well with that of tests. Further numerical parameter analysis for the LFRC beam specimens is conducted. The effects of high-modulus fiber volume fraction on the static behaviors of LFRC beams are studied. The research results show that the additions of high-modulus fibers have little effect on the initial stiffness, yielding loads and ultimate loads of LFRC beams; both the load and displacement at the initial cracking point increase linearly with the increasing volume fraction of the high-modulus fiber, but both the yielding displacement and ultimate displacement decrease linearly with the increasing volume fraction of the high-modulus fiber.

Minimum thickness of concrete members reinforced with fibre reinforced polymer bars

2001 ◽  
Vol 28 (4) ◽  
pp. 583-592 ◽  
Author(s):  
Amin Ghali ◽  
Tara Hall ◽  
William Bobey
Keyword(s):  
Reinforced Concrete ◽  
Minimum Thickness ◽  
Reinforced Polymers ◽  
Flexural Members ◽  
Steel Reinforced Concrete ◽  
Concrete Members ◽  
Reinforced Polymer ◽  
Steel Bars ◽  
Fibre Reinforced Polymer ◽  
Frp Bars

To avoid excessive deflection most design codes specify the ratio (l/h)s, the span to minimum thickness of concrete members without prestressing. Use of the values of (l/h)s specified by the codes, in selecting the thickness of members, usually yields satisfactory results when the members are reinforced with steel bars. Fibre reinforced polymer (FRP) bars have an elastic modulus lower than that of steel. As a result, the values of (l/h)s specified in codes for steel-reinforced concrete would lead to excessive deflection if adopted for FRP-reinforced concrete. In this paper, an equation is developed giving the ratio (l/h)f for use with FRP bars in terms of (l/h)s and (εs/εf), where εs and εf are the maximum strain allowed at service in steel and FRP bars, respectively. To control the width of cracks, ACI 318-99 specifies εs = 1200 × 10–6 for steel bars having a modulus of elasticity, Es, of 200 GPa and a yield strength, fy, of 400 MPa. At present, there is no value specified for εf; a value is recommended in this paper.Key words: concrete, cracking, deflection, fibre reinforced polymers, flexural members, minimum thickness.

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