Load-carrying capacity of GFRP bars under combined axial force–transverse force loading

2013 ◽  
Vol 44 (1) ◽  
pp. 167-171 ◽  
Author(s):  
Andrin Herwig ◽  
Masoud Motavalli
2012 ◽  
Vol 479-481 ◽  
pp. 925-931
Author(s):  
Lei Lei ◽  
Ying Tao ◽  
Tian Min Guan

In order to balance the force loading on the dowel pin , improve the load carrying capacity on pin-hole type output mechanism the FA cycloid drive, we considered to add uniform loading ring on the cantilever end of the pins in this paper. Under the action of uniform loading ring, we did the stress and deformation analysis on the dowel pin; Through the examples comparison we found that, the maximum bending stress of the dowel pin is reduced by 77.86% after adding the uniform loading ring, the dowel pin stress is well-distributed, and the bending strength of output mechanism is improved, thus the load carrying capacity of overall unit is improved.


In this paper, 1 group of plain concrete square columns 150×150×600 mm and 11 groups of concrete columns reinforced with glass fiber reinforced polymer (GFRP) were cast and tested, each group contains of 3 specimens. These experiments investigated effect of the main reinforcement ratio, stirrup spacing and contribution of longitudinal GFRP bars on the load carrying capacity of GFRP reinforced concrete (RC) columns. Based on the experiment results, the relationship between load-capacity and reinforcement ratio and the plot of contribution of longitudinal GFRP bars to load-capacity versus the reinforcement ratio were built and analyzed. By increasing the reinforcement ratio from 0.36% to 3.24%, the average ultimate strain in columns at maximum load increases from 2.64% to 75.6% and the load-carrying capacity of GFRP RC columns increases from 3.4% to 25.7% in comparison with the average values of plain concrete columns. Within the investigated range of reinforcement ratio, the longitudinal GFRP bars contributed about 0.72%-6.71% of the ultimate load-carrying capacity of the GFRP RC columns. Meanwhile, with the same configuration of reinforcement, contribution of GFRP bars to load-carrying capacity of GFRP RC columns decreases when increasing the concrete strength. The influence of tie spacing on load-carrying capacity of reinforced columns was also taken into consideration. Additionally, experimental results allow us to propose some modifications on the existing formulas to determine the bearing capacity of the GFRP RC column according to the compressive strength of concrete and GFRP bars.


2013 ◽  
Vol 838-841 ◽  
pp. 503-509
Author(s):  
Jie Luo ◽  
Jian Chun Xiao ◽  
Zhe Lu ◽  
Xiao Xiao Wei ◽  
Hong Xi Li ◽  
...  

To study the ultimate load-carrying capacity of pipe-plate Vierendeel truss joints, the analyses of joint failure modes and parameter effects were undertaken using nonlinear finite element method and uniform design approach. The plate instability was included in the failure modes. Factors such as the pipe diameter, the pipe thickness, the plate width, the plate height, and the plate thickness were considered in the joint models. Three kind of loading conditions on the plate, the axial force, the moment, the composed loading of axial force and moment were analyzed. The relationships between the joint failure modes and the factors are achieved. The joint ultimate load-bearing capacity formulas are proposed by regression analysis. The effects of factors on the joint strength are illustrated.


2019 ◽  
Vol 2019 ◽  
pp. 1-21 ◽  
Author(s):  
Ali Raza ◽  
Qaiser uz Zaman Khan ◽  
Afaq Ahmad

The present work demonstrates the nonlinear finite element analysis (NLFEA) of 13 concentrically and eccentrically loaded short rectangular concrete column specimens reinforced with GFRP and conventional steel bars. GFRP bars are lightweight having the high tensile strength and high corrosion resistance. An NLFEA model for the rectangular concrete specimens was developed using the commercial software ABAQUS Standard and calibrated for different materials and geometric parameters based on the previous experimental test results of the studied specimen. The behavior of reinforced concrete was modelled using the concrete damaged plasticity (CDP) model, the behavior of steel bars was simulated as a bilinear elastoplastic material, and the GFRP bars were considered as a linear elastic material. After the calibration of CDP parameters, the control sample was used for the further numerical parametric analysis to investigate the effect of critical parameters, i.e., the area of concrete (Ac), the compressive strength of concrete (fc′), and the ratio of longitudinal reinforcement (ρl) and transverse reinforcement (ρt) on the load-carrying capacity of columns. The results show that the selected NLFEA model can simulate the behavior of columns accurately and there was good agreement of numerical results obtained from ABAQUS Standard with the experimental results.


2014 ◽  
Vol 41 (4) ◽  
pp. 368-379 ◽  
Author(s):  
H. Khederzadeh ◽  
K. Sennah

One of the main factors concerning durability and service life of steel-reinforced bridges is corrosion of steel bars especially when exposed to a harsh environment. The use of glass fibre reinforcing polymer (GFRP) bars as non-corrosive material has emerged as an innovative solution to corrosion related problems, reduce the maintenance cost, and increase the service life of bridge structures. A recent cost-effective design of PL-3 bridge barrier was developed at Ryerson University incorporating high-modulus GFRP bars with headed ends. This paper presents results of full-scale static tests to collapse performed on the developed PL-3 bridge barrier at interior and exterior locations to investigate the ultimate load carrying capacity to be compared with Canadian Highway Bridge Design Code (CHBDC). The experimental ultimate load carrying capacity of the barriers was observed to be far greater than CHBDC factored design transverse load. The failure pattern was initiated by a trapezoidal crack pattern at the front face of the barrier, followed by punching shear failure at the transverse load location. Based on the punching shear failure developed in the barrier wall and comparison with available punching shear equations in the literature, an empirical punching shear equation is proposed to determine the transverse load carrying capacity of PL-3 bridge barrier walls reinforced with GFRP bars.


Fibers ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 53
Author(s):  
Nameer A. Alwash ◽  
Mohammed M. Kadhum ◽  
Ahmed M. Mahdi

The efficiency of external strengthening using CFRP (Carbon Fiber Reinforced Polymer) sheets to rehabilitate corrosion-defected RC (Reinforced Concrete) beam–column members is experimentally studied. ALL specimens were tested under a combined axial force and transverse load until failure. The axial forces were applied with two levels either 25% or 50% of the ultimate design load of control specimen. The accelerated corrosion process was used to get steel reinforcement corrosion inside the concrete at three levels, 0% and approximately 5% and 20%, according to Faraday’s law. External strengthening with a CFRP sheet was used in this study to overcome the effect of deterioration in the mechanical properties of the corroded steel bars. A significant deterioration in the load carrying capacity, stiffness, and serviceability was recorded for corrosion-defected specimens. The increase of the axial force was recorded as a positive effect on the ultimate strength, stiffness, and serviceability of the testing specimens. This effect was clearly evident for the defected specimens, with an increasing corrosion level, by decreasing the adverse effects of corrosion. The external strengthening with a CFRP sheet restored the load-carrying capacity, stiffness, and serviceability to an undamaged state.


2016 ◽  
Vol 821 ◽  
pp. 709-716 ◽  
Author(s):  
Petr Janas ◽  
Lenka Koubova ◽  
Martin Krejsa

The paper deals with the calculation of the load carrying capacity of the steel arch reinforcements of underground and mine works with respect to the resulting large displacement and physical nonlinearities. Solution is based on the application of the so-called effective bending stiffness, which is defined as a function of the axial force and bending moment. The numerical model was verified using the values of the load carrying capacity, which have been experimentally obtained using strain-stress test, and implemented into the software that allows very effectively calculate load carrying capacity of steel arch reinforcements.


2012 ◽  
Vol 517 ◽  
pp. 850-857
Author(s):  
Xian Li ◽  
Heng Lin Lv ◽  
Shu Chun Zhou

Fiber-reinforced polymer (FRP) bars are emerging as a competitive option for replacing steel bars as reinforcement in various concrete structures exposed to aggressive environments. However, the low elastic modulus and brittleness of FRP bars significantly reduce the stiffness and the ductility of FRP-reinforced concrete (FRP-RC) members. In order to improve the flexural behavior of FRP-RC members and meanwhile ensure their satisfactory corrosion-resistant performance, an innovative FRP-reinforced concrete encased steel composite (FRP-RCS) member, which consists of ductile structural steel shapes in combination with corrosion-resistant FRP-reinforced concrete, was conceived and studied. An experimental investigation on the flexural behavior of the proposed FRP-RCS beams was conducted by testing a total of five large-scale simply supported beam specimens subjected to four-point bending loads. The test specimens included one FRP-RC beam reinforced with GFRP bars only and four FRP-RCS beams reinforced with both GFRP bars and encased structural steel shapes. The main parameters considered in this study were concrete compressive strength and amounts of GFRP reinforcement. The test results indicated that using encased steel shapes provided a significant enhancement in load carrying capacity, stiffness, ductility and energy absorption capacity of test beams. The tested FRP-RC beam suffered a brittle failure caused by sudden fracture of tensile GFRP bars whereas the proposed FRP-RCS beams behaved in a ductile manner due to the beneficial residual strength of encased steel shapes following concrete crushing. In addition, the experimental results also demonstrated that the concrete compressive strength had little effect on load carrying capacity of FRP-RCS beams whereas the load carrying capacity can be enhanced by increasing the reinforcement ratio. Analytical methods were also constructed using OpenSEES2.2.2 to simulate the load-deflection response of tested beams..


2005 ◽  
Vol 10 (2) ◽  
pp. 151-160 ◽  
Author(s):  
J. Kala ◽  
Z. Kala

Authors of article analysed influence of variability of yield strength over cross-section of hot rolled steel member to its load-carrying capacity. In calculation models, the yield strength is usually taken as constant. But yield strength of a steel hot-rolled beam is generally a random quantity. Not only the whole beam but also its parts have slightly different material characteristics. According to the results of more accurate measurements, the statistical characteristics of the material taken from various cross-section points (e.g. from a web and a flange) are, however, more or less different. This variation is described by one dimensional random field. The load-carrying capacity of the beam IPE300 under bending moment at its ends with the lateral buckling influence included is analysed, nondimensional slenderness according to EC3 is λ¯ = 0.6. For this relatively low slender beam the influence of the yield strength on the load-carrying capacity is large. Also the influence of all the other imperfections as accurately as possible, the load-carrying capacity was determined by geometrically and materially nonlinear solution of very accurate FEM model by the ANSYS programme.


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