Experimental research on I-girders subjected to eccentric patch loading

This paper presents the results of the experimental research performed on the thin-walled I-profiles subjected to patch loading. The experiment was divided into two phases. During the first one the behaviour of girders subjected to loading in the plane of the web was studied, and during the second phase, girders subjected to loading showing certain eccentricity in relation to the web plane were analysed. Thirty-six tests were performed. This paper analyses the results of girders under eccentric loading. The girders were tested to final collapse. The failure load is smaller under certain conditions than in cases with concentric load. Girder collapse form differs considerably from the collapse form of the concentrically loaded beams. Carrying capacity loss in the case of concentrically loaded girders is due to web buckling, while in the case of eccentrically loaded beams we consider the problem of carrying capacity loss due to local elasto-plastic bending. During the process of load increase the most evident deformation is flange warping accompanied by gentle web bending, which follows flange deformation. Flange warping and web bending grow until final collapse of girder. The most important question which is to be investigated in the future is under what conditions and what combinations of different parameters and eccentricity values the collapse form will be of the same kind as with concentrically loaded girders.