The results of experimental and analytical study on the behavior of reinforced concrete beams strengthened with the fiber reinforced polymer (FRP) for flexure are discussed in this paper. A test series comprising four five meters long simply supported beams were tested under monotonic load to verify the analytical model. Particular emphasis was given to the performance of predicted model building upon discrete element analytical methodology incorporating the dual effects of flexure and shear in beams. An important conclusion in this paper is that the predicted model can be used to accurately predict the flexural behavior of load versus displacement and FRP bonded stresses.
The corrosion of steel reinforcing bars in offshore reinforced concrete (RC) structures has been a serious problem for maintaining the service life of the RC infrastructures. Nowadays, using fiber-reinforced polymer (FRP) composites as strengthening materials of the corrosive offshore RC structures is one of the most beneficial ways and perhaps more reliable than any alternative materials. In the study, prediction on the flexural behavior of as-built RC beams strengthened with the FRP composites is concerned. Analytical prediction of the flexural strength of RC beams with FRP composites has been mainly based on two approaches. The first approach used non-linear finite element analysis (Malek, 1998; Nitereka, 1999). Such approach is complex, time consuming, sensitive to element modelling and, at present, does not always lead to reliable predictions. Arduini and Nanni (1997) developed a second approach, termed the discrete element analysis. This is a rather simple model that accounts for the mechanical properties of the constituent materials and the characteristics of the concrete-to-FRP interface. This approach can be used to find the maximum bond stresses at the FRP plate and concrete interface as well as the bond stress distribution at the interface throughout the beam length.