Experiments on Box Type Girders

Abstract

In order to study the strength and the rigidity etc. of box type girders for overhead travelling cranes, full-sized model experiments were conducted. Two model girders were used. The upper deck and the two web plates of one model (Girder 2) were reinforced by longitudinal stiffeners, while those of the other (Girder 1) were not. Load was applied on top of the inner web plate at the center of the span of each girder, which was supported at its ends. Results are as follows : (1) The stress distributions on the plate surfaces were generally irregular, while deflections, buckling loads, failure loads of girders and shapes of plates after failures were coincident with their calculated values. (2) The effects of longitudinal stiffeners on the strength of Girder 2 appeared clearly. (3) The torsion produced by the eccentric load has not a remarkably bad effect on a box type girder of such dimension ratio as used in the present experiments.