Large Curvature Continuous Steel Box Girder Bridge Shear Lag Effect In Experimental Research

The application of continuous steel box girders with large curvature is apparently wide in construction of city viaducts and crossroads. But the shear lag effect is often ignored in common engineering design just because of the deficiency of specifications for it in JTJ023-85.In this paper, the shear lag effect of continuous steel box girder with large curvature under concentrated force and uniformly distributed load was discussed through model experiments and using spatial finite element method. Based on the analysis and experiment a kind of compensation factor was used to take the initial bending of the steel plate into consideration and the varying pattern of the shear lag coefficient was found, which can be used in engineering design to guarantee the safety of the bridges. The other three box girder models with different number of cells varying from one to three were established using spatial finite element method based on the model with four cells, left all the other influencing factors unchanged. The shear lag effect of the three models was discussed and the varying pattern of the shear lag coefficient was found. In the mean while the two kinds of definitions of the shear lag coefficient for curved girders were also discussed.