Bond Behaviour of GFRP Bars with Concrete at Normal and High Temperatures

2021 ◽  
pp. 275-286
Author(s):  
Jahanzaib ◽  
Shamim A. Sheikh ◽  
Zahra Kharal ◽  
Husham Almansour
Keyword(s):  
High Temperatures ◽  
Bond Behaviour ◽  
Gfrp Bars

Experimental Research on Mechanical Behavior of GFRP Bars under High Temperature

2011 ◽  
Vol 71-78 ◽  
pp. 3591-3594 ◽  
Author(s):  
Xiao Lu Wang ◽  
Xiao Xiong Zha
Keyword(s):  
Glass Transition ◽  
High Temperature ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Epoxy Resin ◽  
High Temperatures ◽  
Glass Fibers ◽  
Ultimate Tensile Stress ◽  
Gfrp Bars ◽  
Tensile Test Result

Experimental results on tensile mechanics properties of GFRP bars at high temperatures are present in this paper. Thirty commercially produced GFRP tensile specimens of 8mm diameter were tested at high temperature ranging from 10°Cup to 500°C. Tensile test result indicates that, the ultimate tensile stress has significant reduction at two temperature zones, one is glass transition temperature of epoxy resin (80-120°C), with strength degradation 22%, the second is the soften temperature of glass fibers(about 400°C), the strength decrease drastically with almost linear rate and remained 33% residual strength at 500°C. The elastic modulus remained unchanged until glass transition temperature of epoxy resin, and the modulus declined linearly with the temperature elevating. Stress-strain relationships of GFRP bars exhibit liner performance even at high temperatures.

Influence of Test Configuration on Bond Strength of GFRP Bars

2019 ◽  
Vol 292 ◽  
pp. 217-223 ◽  
Author(s):  
Ondřej Janus ◽  
Frantisek Girgle ◽  
Vojtech Kostiha ◽  
Petr Štěpánek ◽  
Pavel Sulak
Keyword(s):  
Bond Strength ◽  
Concrete Cover ◽  
Silica Sand ◽  
Beam Test ◽  
Bond Behaviour ◽  
Test Configuration ◽  
Gfrp Bars ◽  
Pull Out ◽  
Frp Reinforcement ◽  
Gfrp Reinforcement

It is well-known that test configuration affects bond behaviour of steel reinforcement, but this effect has not yet been sufficiently quantified when using FRP reinforcement. This paper presents partial results from an ongoing experimental programme that deals with the bond strength of GFRP bars with concrete, with regards to the effect of the surface treatment of the rebars and test configuration. A modified beam test is presented in this study along with a pull-out test with an eccentric bar placement. The bond strength of GFRP reinforcement with sand-coated treatment using silica sand and ribbed type with milled ribs was tested. The sand-coated bars exhibit different bond behaviour compared to the ribbed ones due to different forces transfer from the reinforcement to the concrete. Thickness of the concrete cover layer also has a significant effect on the bond behaviour of the reinforcement.

scholarly journals Bond characteristics of glass fibre reinforced polymer bars embedded in high performance and ultra-high performance concrete

2021 ◽  
Author(s):  
Dave Ametrano
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Ultra High Performance Concrete ◽  
Bond Behaviour ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Glass Fibre Reinforced Polymer ◽  
Fibre Reinforced Polymer ◽  
Glass Fibre Reinforced ◽  
Bond Characteristics

The use of fibre reinforced polymer (FRP) bars is increasing in construction as an alternative to conventional steel rebars. This thesis investigates the bond behaviour of glass fibre reinforced polymer (GFRP) bars embedded in high performance concrete (HPC) and ultra-high performance concrete (UHPC). In this study, the bond characteristics of sand coated GFRP bars embedded in 70-175 MPa concrete were explored. Beam and pullout tests were performed to determine the effects of the concrete strength, bar diameter, embedment length, and concrete cover on the bond behaviour of GFRP bars. Based on the analysis, the development lengths for the GFRP bars were determined and then compared to requirements provided by design codes. It was concluded that the design code lengths could be reduced by 20% while still maintaining a factor of safety of two over the development lengths determined through this study. This reduction can be applied when the GFRP bar is surrounded by sufficient transverse reinforcement, such that adding additional reinforcement would not affect the bond strength. Reducing the amount of GFRP reinforcing material needed, results in a lower overall cost of construction.

Bond behaviour of GFRP bars in high-strength concrete: bar diameter effect

2017 ◽  
Vol 69 (11) ◽  
pp. 541-554 ◽  
Author(s):  
Jung-Yoon Lee ◽  
A-Ra Lim ◽  
Jinyoung Kim ◽  
Jeongho Kim
Keyword(s):  
High Strength Concrete ◽  
High Strength ◽  
Bond Behaviour ◽  
Strength Concrete ◽  
Gfrp Bars ◽  
Bar Diameter ◽  
Diameter Effect

scholarly journals Beam Bond Tests of GFRP and Steel Reinforcement to Concrete

2018 ◽  
Vol 64 (4) ◽  
pp. 243-256
Author(s):  
D. Szczech ◽  
R. Kotynia
Keyword(s):  
Reinforced Concrete ◽  
Surface Preparation ◽  
Steel Reinforcement ◽  
Experimental Program ◽  
Bond Behaviour ◽  
Gfrp Bars ◽  
Concrete Members ◽  
Glass Fiber Reinforced ◽  
Steel Bars ◽  
Frp Bars

AbstractThe paper presents research program of bond between glass fiber reinforced polymer bars and concrete in reference to the steel bars. Bond between the reinforcement and concrete is a crucial parameter governing a behaviour of reinforced concrete members and transferring of the internal forces from concrete to the reinforcement. The use of FRP bars as an equivalent reinforcement to steel in concrete structures has increased in recent years. The FRP bars are very different from steel, mainly due to much lower elasticity modulus and their anisotropic structure. Good performance of FRP reinforced concrete requires sufficient interfacial bond between bars and concrete. However, there are no specific standards referring to the surface preparation of these bars, that leads to variable bond behaviour of the composite reinforcement to the concrete. The objective of the study was to investigate the influence of variable parameters on the bond behaviour to concrete. The experimental program consisted of eighteen beam bond specimens varying in: bar diameter (12mm, 16mm, 18mm) and type of reinforcement (GFRP sand – coated and steel bars). Although the GFRP bars indicated good bond behaviour to concrete, the average bond strength was slightly lower than that of steel reinforcement of 16mm and 18 mm, while it was higher for the GFRP bars of 12mm diameter.

scholarly journals Investigation of pullout strength of pre-installed glass fibre reinforced polymer bars in high-performance concrete

2021 ◽  
Author(s):  
Jennifer Lu
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Concrete Cover ◽  
Bond Behaviour ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Glass Fibre Reinforced Polymer ◽  
Concrete Blocks ◽  
Fibre Reinforced Polymer

Fibre reinforced polymer (FRP) bars are rapidly becoming an alternative to conventional steel reinforcing bars in bridge construction. This research investigated the bond behaviour of glass fiber reinforced polymer (GFRP) bars embedded in high-­‐performance concrete (HPC). Sand-­‐coated and ribbed-­‐surface GFRP bars of 16 and 20 mm diameters were considered in this study. Concrete blocks were cast with embedded GFPR bars to conducted pullout tests to examine the effect of varying parameters on their pullout and bond strengths, namely: embedment length, bar diameter, surface treatment, and concrete cover. In addition, bond characteristic were analyzed between straight and head-­‐ended sand-­‐coated GFRP bars. The experimental results were used to evaluate the development lengths specified in design codes. It was determined that the development lengths for straight GFRP bars provided by the codes are conservative. Also, the development length for head-­‐end bar is shorter than that for similar bar with straight end.

scholarly journals Effect of temperature on the bond behaviour of GFRP bars in concrete

2020 ◽  
Vol 183 ◽  
pp. 107602 ◽  
Author(s):  
Sandor Solyom ◽  
Matteo Di Benedetti ◽  
Maurizio Guadagnini ◽  
György L. Balázs
Keyword(s):  
Effect Of Temperature ◽  
Bond Behaviour ◽  
Gfrp Bars

Influence of elevated temperatures on the bond behaviour of ribbed Gfrp bars in concrete

2021 ◽  
pp. 104119
Author(s):  
Inês C. Rosa ◽  
João P. Firmo ◽  
João R. Correia ◽  
Pietro Mazzuca
Keyword(s):  
Elevated Temperatures ◽  
Bond Behaviour ◽  
Gfrp Bars

scholarly journals Influence of Bond Behaviour of Flexural GFRP Reinforcement on Failure Mechanisms in Beams Without Stirrups

2018 ◽  
Vol 64 (4) ◽  
pp. 269-283
Author(s):  
M. Kaszubska ◽  
R. Kotynia
Keyword(s):  
Shear Strength ◽  
Failure Mode ◽  
Failure Modes ◽  
Shear Failure ◽  
Shear Crack ◽  
Failure Mechanisms ◽  
Crack Pattern ◽  
Critical Crack ◽  
Bond Behaviour ◽  
Gfrp Bars

AbstractThe aim of the paper is to investigate the shear failure mechanisms in T-shape, single span and simply supported beams exclusively reinforced with longitudinal glass fiber reinforced polymer (GFRP) bars. Usually the critical shear crack in RC beams without stirrups develops through the theoretical compression strut reducing the shear strength following the shear failure. The main parameter affecting the crack pattern and the shear strength of the beams is the shear slenderness. However, the test results presented in the paper indicated the new arching effect due to the bond losing between the GFRP flexural reinforcement and concrete. This failure mode revealed unexpected critical crack pattern and failure mode. The research of concrete beams flexurally reinforced with GFRP bars without stirrups indicated two failure modes: typical shear-compression and a new one leading by the bond losing between the ordinary reinforcement and concrete.

Sign in / Sign up

Export Citation Format

Share Document