Research Articles | Challenge Journal of Concrete Research Letters

Strengthening of Concrete Beams Using FRP Composites

Ahmed A. Elshafey, Medhat Mohammed, Mostafa M. El-Shami, Kamel S. Kandil


Finite element analysis (FEA) is used to predict the behavior of reinforced concrete beams strengthened with fiber reinforced polymer (FRP). To verify and measure the accuracy of the FEM model, the current model results were compared with both experimental and theoretical available results. Four beams were studied simulating the Horsetail Creek Bridge, Oregon, USA. The first one is a control beam with no strengthening fiber.The second beam is strengthened with carbon fiber reinforced polymer (CFRP) oriented along the length of the beam to reinforce the flexure behavior. The third beam is wrapped with glass fiber reinforced polymer(GFRP) laminates representing the shear beam. The fourth one is strengthened with CFRP and GFRP laminates representing the flexure-shear beam.The load-strain for concrete, steel and fiber as well were represented and compared. In addition, the load deflection curves and crack patterns were developed and represented. The results showed that the modeling process was accurate in simulating the tested beams. It was also clear that using FRP in strengthening reinforced concrete beams is an effective method in improving both shear and flexural behavior of the beams.


CFRP; GFRP; finite element; strengthening; concrete; beam

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