Experimental Investigations on Behaviour of Shear Deficient Reinforced Concrete Beams Under Monotonic and Fatigue Loading

The strengthening of reinforced concrete members with prestressed fibre-reinforced polymer laminates has been investigated by researchers due to major improvements in member serviceability characteristics. Currently, analytical models generally employ mostly empirical procedures in predicting member behaviour, and as a result, the analytical results exhibit poor correlation to experimental investigations. In this article, an analytical model is developed using new and existing theoretical techniques to critically analyse strengthened reinforced concrete beams for a range of loading scenarios to generate moment–rotation and load–deflection relationships. The prestress level and the intermediate crack debonding strain of the prestressed fibre-reinforced polymer laminate with the inclusion of mechanical end anchorage were highlighted as key parameters within the model. The proposed model adopts closed-form solutions to allow for a wide range of beams with varying steel and fibre-reinforced polymer reinforcement ratios and dimensions. The model incorporates calibrated crack spacing theory to predict the crack width and spacing as well as the length of the cracked region in the beam. The models have good correlation with collected experimental data and thus can be used for the analysis of reinforced concrete beams strengthened with prestressed fibre-reinforced polymer, throughout all stages of loading from serviceability to failure.

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DEFLECTION OF FLEXURAL REINFORCED CONCRETE STRUCTURES WITH EXTERNAL NON-METALLIC REINFORCEMENT (EXPERIMENTAL AND THEORETICAL INVESTIGATION)

Journal of Civil Engineering and Management ◽

10.3846/13923730.2002.10531272 ◽

2002 ◽

Vol 8 (3) ◽

pp. 164-168

Author(s):

Juozas Valivonis

Keyword(s):

Reinforced Concrete ◽

Theoretical Investigation ◽

Concrete Beams ◽

Theoretical Calculations ◽

Concrete Structures ◽

Reinforced Concrete Beams ◽

Experimental Investigations ◽

Reinforced Concrete Structures ◽

Metallic Reinforcement ◽

Good Agreement

In many cases concrete structures with prestressed steel being sufficiently strong do not meet requirements for stiffness. It is possible to avoid steel prestressing in concrete structures by means of providing additional non-metallic reinforcement, which gives opportunity to increase stiffness of beams significantly. Experimental investigations of reinforced concrete beams with external non-metallic reinforcement were made. Method for calculation of deflection of beams with external non-metallic reinforcement is presented in this article. Theoretical calculations of deflections using the proposed method were performed. Sufficiently good agreement with experimental deflection values was obtained.

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A Parametric Study on the Flexural Strengthening of Reinforced Concrete Beams with Near Surface Mounted FRP Bars

Civil Engineering Journal ◽

10.28991/cej-03091126 ◽

2018 ◽

Vol 4 (8) ◽

pp. 1917

Author(s):

Minu Panahi ◽

Mohsen Izadinia

Keyword(s):

Reinforced Concrete ◽

Concrete Beams ◽

Weight Ratio ◽

Bending Moment ◽

Reinforced Concrete Beams ◽

Flexural Behavior ◽

Experimental Investigations ◽

Near Surface ◽

Finite Element Software ◽

Near Surface Mounted

FRP rods as lightweight materials with extraordinary properties of high strength to weight ratio, corrosion resistance, potentially high overall durability, tailor ability and high specific attributes are one of the most favorable materials to strengthen existing reinforced structures. The present study aimed to identify the behavior of reinforced concrete flexural beams strengthened with fiber reinforced polymer (FRP) rods through near surface mounted method (NSM). The results of the current study were based on nonlinear finite element software ABAQUS which can accurately simulate the experimental investigations on flexural behavior of reinforced concrete beams strengthened with NSM FRP rods. Validation of the proposed model was confirmed first by making a comparison with the experimental study presented in the literature. A parametric analysis was conducted on validated specimens to investigate the effect of FRP rod diameters, rod arrangements, FRP materials, as well as rods groove intervals on flexural behavior of strengthened reinforced beams. The numerical results of mid-span bending moment deflection, ultimate bending moment, failure deflection and ductility index were reported. For the sake of simplicity to be used by engineers, the results of the current study were drawn in the form of design charts and tables.

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