FE Models of GFRP and CFRP Strengthening of Reinforced Concrete Beams

Abstract

Three-dimensional finite element (FE) models are developed to simulate the behavior of full-scale reinforced concrete beams strengthened with glass and carbon fiber-reinforced polymer sheets (an unstrengthened control beam, a flexural-strengthened beam, a shear-strengthened beam, and a beam with both shear and flexural strengthening). FE models use eight-node isoparametric elements with a smeared cracking approach for the concrete and three-dimensional layered elements to model the FRP composites. Analysis results are compared with data obtained from full-scale beam tests through the linear and nonlinear ranges up to failure. It was found that the FE models could identify qualitatively trends observed in the structural behavior of the full-scale beams. Predicted crack initiation patterns resemble the failure modes observed for the full-scale beam tests.