A finite element with exact shape functions for shear lag analysis in multi-cell box girders

Vlasov's thin-walled beam theory is combined with special shear lag warping functions to derive a box beam finite element with exact shape functions which can be used to analyze single- and multi-cell box girders. The fundamental theory of this model is rigorous and the governing differential equations are solved exactly. A computer program based on the proposed model has been developed for the analysis of single- or multi-cell box girder bridges. Examples are presented which compare the proposed method with the facet shell finite element analysis, with good agreement between the two sets of results.