A finite beam element for analyzing shear lag and shear deformation effects in composite-laminated box girders

This paper presents the initial-value solutions of static equilibrium differential equations of single-cell thin-walled composite-laminated box beams under bending loads with consideration of both shear lag and shear deformation. The initial-value solutions is used to establish the related element stiffness matrix and equivalent nodal forces vector, so that the analysis of shear lag and shear deformation effects in composite-laminated box girders is admitted into the program system of the finite beam element method. The procedure of this paper can be used to analyze effectively the mechanical behaviors of some complex composite structures (such as continuous laminated box girders, etc.).