scholarly journals Optimization of Fiber-Reinforced Polymer Bars for Reinforced Concrete Column Using Nonlinear Finite Element Algorithms

Algorithms ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 12
Author(s):  
Sajjad Sayyar Roudsari ◽  
Liviu Marian Ungureanu ◽  
Soheil Soroushnia ◽  
Taher Abu-Lebdeh ◽  
Florian Ion Tiberiu Petrescu
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Optimization Technique ◽  
Fiber Reinforced Polymer ◽  
Plastic Behavior ◽  
Fiber Reinforced ◽  
Rc Columns ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Steel Bars

The ductility and strength of reinforced concrete (RC) columns could be noticeably improved by replacing steel bars with polymeric bars. Despite the previous research on RC columns, most of those studies focused only on the lateral load capacity of this structural member and were mainly costly experimental studies. However, this paper is concentrated on the previously occurred damages to the reinforced columns in the previous earthquakes. Subsequently, finite element analysis has been performed to examine 24 models including the various shapes of RC columns. In employing the plastic behavior of steel, carbon fiber-reinforced polymer (CFRP), and glass fiber reinforced polymer (GFRP) bars, the bilinear hardening has been considered. To capture both compressive and tensile behavior of the concrete, the concrete damage plasticity model has been implemented. Furthermore, the optimization technique is used for CFRP models to compare with other models. In this paper, the parameters of energy, seismic factor, stiffness, and ductility have been computed using the method proposed by the authors. This suggested method is considered to compare the results from each parameter. Finite element results of steel bars are compared with carbon and glass models. The results show the stiffness of models is improved by CFRP bars, while the energy absorption and ductility factor are enhanced with steel bars. Moreover, GFRP bars can enhance the seismic factor. The reduction of column stiffness to almost half would occur in some rectangular cross-section columns.

Flexural Behaviour of Reinforced Concrete Beam with Glass Fiber Reinforced Polymer (GFRP) Bar Strengthened with Carbon Fiber Reinforced Polymer (CFRP) Plate

2014 ◽  
Vol 1051 ◽  
pp. 748-751 ◽  
Author(s):  
Norhafizah Salleh ◽  
Abdul Rahman Mohd Sam ◽  
Jamaludin Mohd Yatim ◽  
Mohd. Firdaus bin Osman
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beam ◽  
Reinforced Concrete Beam ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Cfrp Plate ◽  
Glass Fiber Reinforced ◽  
Steel Bars

The use of glass-fiber-reinforced polymer (GFRP) bar to replace steel reinforcement in concrete structures is a relatively a new technique. The GFRP bars possess mechanical properties different from steel bars, including high tensile strength combined with low elastic modulus and linear stress–strain relationship up to failure. Therefore, design procedures and process should account for these properties. This paper presents the experimental work on the flexural behavior of concrete beam reinforced with GFRP bars and strengthen with CFRP plate. A total of ten reinforced concrete beams reinforced with either steel and GFRP bars were cast and tested under four point loads. Eight concrete beams (200x250x2800mm) were reinforced with 13mm diameter GFRP bars together with strengthening using CFRP plate and two control beams reinforced with 12mm diameter steel bars were tested. The experimental results show that although the stiffness of the beams reduced but the ultimate load of the GFRP reinforced concrete beam is bigger than steel reinforced beam. It was also found that strengthening using CFRP plate will further enhanced the flexural performance of the beams with GFRP bars.

Simulation Behavior of Flexure in Reinforced Concrete Beam with Opening Reinforced with Glass Fiber Reinforced Polymer (GFRP)

2016 ◽  
Vol 857 ◽  
pp. 421-425
Author(s):  
Saif M. Thabet ◽  
S.A. Osman
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Glass Fiber ◽  
Concrete Beam ◽  
Reinforced Concrete Beam ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced Polymer ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced

This paper presents an investigation into the flexural behaviour of reinforced concrete beam with opening reinforced with two different materials i.e., steel and Glass Fiber Reinforced Polymer (GFRP). Comparison study between the two different materials were carried out and presented in this study through non-linear Finite Element Method (FEM) using the commercial ABAQUS 6.10 software package. The performance of the opening beam reinforced with GFRP is influenced by several key parameters. Simulation analyses were carried out to determine the behavior of beam with opening subjected to monotonic loading. The main parameters considered in this study are size of opening and reinforcement diameter. The results show that GFRP give 23%-29% more ductility than steel reinforcement. The result also shows when the size of opening change from 200mm to 150mm or from 150mm to 100mm the ultimate load capacity increase by 15%. In general, good agreement between the Finite Element (FE) simulation and the available experimental result has been obtained.

NUMERICAL ANALYSIS OF CONCRETE BEAM REINFORCED WITH GLASS FIBER REINFORCED POLYMER BARS

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Osama A. Mohamed ◽  
Rania Khattab
Keyword(s):  
Finite Element ◽  
Numerical Analysis ◽  
Concrete Beam ◽  
Concrete Beams ◽  
Fiber Reinforced Polymer ◽  
Reinforcing Bars ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Steel Bars ◽  
Frp Bars

The use of fiber reinforced polymer (FRP) bars to reinforce concrete beams has received significant attention in the past decade due to their corrosion resistance, high tensile strength, and excellent non-magnetic properties. Glass FRP (GFRP) reinforcing bars have gained popularity due to the relatively lower cost compared to carbon FRP (CFRP) bars. In this study, sixteen concrete beam finite element models were created using the finite element computer program ANSYS to perform linear and non-linear analyses. Twelve beams were longitudinally reinforced with GFRP bars, while the remaining four beams were reinforced with conventional steel bars as control specimens. In terms of mechanical properties, FRP reinforcing bars have lower modulus of elasticity compared to conventional reinforcing steel and remain linear elastic up to failure. This leads to lack of plasticity and a brittle failure of beams reinforced with FRP bars. The objective of this study is to investigate flexural behavior of concrete beams reinforced with GFRP reinforcing bars. Some of the parameters incorporated in the numerical analysis include longitudinal reinforcement ratio and compressive strength of concrete, both of which affect the flexural capacity of beams. It is shown in this study that replacement of traditional reinforcing steel reinforced bars by GFRP bars significantly decreases mid-span deflection and increases ultimate load. The strain distribution along GFRP longitudinal reinforcing bars is totally different from that of traditional steel bars.

scholarly journals Evaluation of Seismic Behaviors of Partially Deteriorated Reinforced Concrete Circular Columns Retrofitted with CFRP

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Dongxu Hou ◽  
Jianyun Pan ◽  
Xinglang Fan ◽  
Zhimin Wu ◽  
Prosper Marindiko
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Concrete Strength ◽  
Fiber Reinforced Polymer ◽  
Carbon Fiber Reinforced Polymer ◽  
Element Analysis ◽  
Rc Columns ◽  
Reinforced Polymer ◽  
Seismic Behaviors ◽  
Failure Location

Deficiency of the concrete strength in some regions of reinforced concrete (RC) columns in practice may weaken the seismic behaviors of columns. Its effects on RC columns should be well understood. This paper aims to investigate the influences of deteriorated segment on the seismic behaviors of partially deteriorated RC columns and attempts to recover the seismic behaviors of partially deteriorated columns with Carbon Fiber Reinforced Polymer (CFRP) composites. A finite element analysis was carried out to simulate the seismic behaviors of CFRP-confined partially deteriorated RC columns. The numerical results were verified by the laboratory tests of six specimens. Based on the finite element results, the failure location of partially deteriorated columns in an earthquake was predicted, and the effectiveness of CFRP retrofitted on partially deteriorated columns was evaluated.

scholarly journals Behavior of reinforced concrete beams reinforced with GFRP bars

2008 ◽  
Vol 1 (3) ◽  
pp. 285-295 ◽  
Author(s):  
D. H. Tavares ◽  
J. S. Giongo ◽  
P. Paultre
Keyword(s):  
Reinforced Concrete ◽  
Structural Engineering ◽  
Concrete Beams ◽  
Steel Reinforcement ◽  
Reinforced Concrete Beams ◽  
Fiber Reinforced Polymer ◽  
Tension Force ◽  
Fiber Reinforced ◽  
Gfrp Bars ◽  
Reinforced Polymer

The use of fiber reinforced polymer (FRP) bars is one of the alternatives presented in recent studies to prevent the drawbacks related to the steel reinforcement in specific reinforced concrete members. In this work, six reinforced concrete beams were submitted to four point bending tests. One beam was reinforced with CA-50 steel bars and five with glass fiber reinforced polymer (GFRP) bars. The tests were carried out in the Department of Structural Engineering in São Carlos Engineering School, São Paulo University. The objective of the test program was to compare strength, reinforcement deformation, displacement, and some anchorage aspects between the GFRP-reinforced concrete beams and the steel-reinforced concrete beam. The results show that, even though four GFRP-reinforced concrete beams were designed with the same internal tension force as that with steel reinforcement, their capacity was lower than that of the steel-reinforced beam. The results also show that similar flexural capacity can be achieved for the steel- and for the GFRP-reinforced concrete beams by controlling the stiffness (reinforcement modulus of elasticity multiplied by the bar cross-sectional area - EA) and the tension force of the GFRP bars.

Tension stiffening and cracking of concrete reinforced with glass fiber reinforced polymer (GFRP) bars

2004 ◽  
Vol 31 (4) ◽  
pp. 579-588 ◽  
Author(s):  
Peter H Bischoff ◽  
Richard Paixao
Keyword(s):  
Reinforced Concrete ◽  
Glass Fiber ◽  
Crack Spacing ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced Polymer ◽  
Tension Stiffening ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced

Tension stiffening and cracking of axial tension members is evaluated for concrete reinforced with steel (reinforcing ratio ρ = 2.0%) and glass fiber reinforced polymer (GFRP) bars (1.3%, 2.0%, and 2.9%), with shrinkage included in the analysis of the member response. Results show that because of a lower bar stiffness the GFRP-reinforced concrete exhibits greater tension stiffening than steel-reinforced concrete for any given value of axial member strain. Transverse cracking in the GFRP-reinforced concrete does not stabilize until much higher values of axial strain are reached, and longitudinal splitting cracks are also evident before cracking has stabilized. Crack widths in concrete reinforced with GFRP bars are larger because of their lower bar stiffness in combination with an increased crack spacing during the crack development stage. Tension stiffening of cracked reinforced concrete is taken into account using an average stress-strain response with a descending branch to model the concrete in tension. A tension stiffening factor is used to characterize this tensile property with an empirical relationship related to the reinforcing bar stiffness and independent of both concrete strength and reinforcing ratio. Results are also compared with the predicted member response based on the 1978 Comité Euro-International du Béton (CEB) CEB-FIP model code approach and American Concrete Institute (ACI) method of using an effective cracked section property for the transformed concrete area. This comparison shows that both methods are valid only for a limited range of reinforcing ratios.Key words: cracking, crack spacing, crack width, GFRP, reinforced concrete, tension stiffening.

Contribution of longitudinal glass fiber-reinforced polymer bars in concrete cylinders under axial compression

2018 ◽  
Vol 45 (6) ◽  
pp. 458-468 ◽  
Author(s):  
Brandon Fillmore ◽  
Pedram Sadeghian
Keyword(s):  
Elastic Modulus ◽  
Glass Fiber ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced Polymer ◽  
Gfrp Bars ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Steel Bars ◽  
Concrete Cylinders

Contribution of longitudinal glass fiber-reinforced polymer (GFRP) bars in concrete columns under compression has been ignored by current design guidelines. This paper challenges this convention by testing 21 concrete cylinders (150 mm × 300 mm) reinforced with longitudinal GFRP and steel bars in compression. It was observed that GFRP bars could sustain high level of compressive strains long after the peak load of the specimens without any premature crushing. The results of a new coupon test method showed that the elastic modulus of GFRP bars in compression is slightly higher than that of in tension, however the compressive strength was obtained 67% of tensile strength. An analytical model was successfully implemented to predict the axial capacity of the tests specimens and it was found that the contribution of the bars in the load capacity of the specimens was within 4.5–18.4% proportional to the bars reinforcement ratio normalized to the elastic modulus of steel bars.

A concentric tube anchor system for fiber-reinforced polymer retrofit of reinforced concrete structural walls under extreme loads

2017 ◽  
Vol 9 (1) ◽  
pp. 77-98 ◽  
Author(s):  
David T Lau ◽  
Joshua E Woods
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Shear Walls ◽  
Fiber Reinforced Polymer ◽  
Experimental Program ◽  
Design Parameters ◽  
Fiber Reinforced ◽  
Anchor System ◽  
Reinforced Polymer ◽  
Polymer Sheets

In reinforced concrete elements strengthened with fiber-reinforced polymer sheets, premature debonding of the fiber-reinforced polymer from the concrete substrate occurs due to lack of anchorage, which reduces the efficiency of the retrofitting system. This article reviews several common anchor systems and describes the development, optimization, and testing of a steel tube anchor in retrofit of reinforced concrete structural elements using externally bonded fiber-reinforced polymer sheets suitable for application to improve resistance against extreme load conditions (e.g. blast, impact, or an earthquake). A detailed review of common anchor designs including the proposed tube anchor based on previous studies on flexure-dominated fiber-reinforced polymer-strengthened reinforced concrete shear walls is presented. In this study, finite element analysis is conducted to verify the observed behavior and better understand the deformation mechanisms of the tube anchor. Finite element modeling is then used to evaluate the influence of different design parameters on its performance and propose a design methodology that can be used to optimize the tube anchor design. To verify the performance of the optimized tube anchor, it is tested in an experimental program on the in-plane seismic strengthening of two shear-dominated squat walls strengthened using fiber-reinforced polymer sheets. Experimental results reveal that the optimized tube anchor performs well in preventing premature debonding and allows the fiber-reinforced polymer composite to achieve a higher level of strain when compared to an alternative anchor system. Finally, a set of design steps for the implementation of the tube anchor in fiber-reinforced polymer retrofit applications for reinforced concrete shear walls are presented.

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