عنوان مقاله [English]
Regarding the vast and suitable application of fiber reinforced polymer (FRP) in the strengthening of concrete structures, the recent idea of using fiber reinforced polymer composites in steel structures has been formed and extended by doing experiments and extensive research. The aim of this present research is to study the strengthening of bending steel beams by composite plates and, also, the rate of increasing the length of the FRP plate on the performance of the strengthened beam. All beams are selected in 1 shape with a length of 2000 mm. So, 6 beams have been tested in this research; 2 beams strengthened with composite plates in the whole length, 2 beams strengthened only in the middle of their length and the other beams loaded without composite plates as the control beams. The retrofitted and control beams were tested under static loading, so, besides preparing the diagram of the force-distance, the yielding load of beams and the failure of composite plates are determined. To verify the results of the experiments, a beam was modeled by the existing finite element software and its force-displacement diagram was compared with the results of the experiment. According to the results, application of composite plates increases the bending capacity of steel beams. Moreover, force-distance diagrams indicate the desirable performance of strengthened beams.