STEEL BOX GIRDERS STIFFENED IN THE COMPRESSION ZONE

Abstract

After the well known accidents on several large span steel box girder bridges, in which an important role was played by the weakness of their compression flanges. The objective of this study is to provide information about the behavior of steel box girders stiffened in the compression zone.

3-D Nonlinear finite element analysis was performed usmg COSMOSMIM program. Five models of steel box girders having a span equal 2600 mm are considered. The studied parameters are: the shape and area of stiffeners in the compression zone of box girders. The results of the finite element analysis are the• ultimate loads, the vertical deflections, and the normal and shear stresses were compared with previous experimental work.

A good agreement of the finite element model with the experimental work was achieved .

• . The finite element model was used for additional extension of the work to study the behavior of steel box girders stiffened in the

compression flanges. The effect of compression flange thickness, tension flange thickness, the stiffener thickness and variation of loading and diaphragm location on the ultimate loads, normal and shear stresses was also investigated .

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