A One-dimensional Model for Thin-walled Box Girder Structures Considering the Deformable Cross-section in Dynamics

Abstract

In this paper, a one-dimensional dynamic model is developed for thin-walled box girders considering both out-of-plane and in-plane cross-section deformations. The model considers the displacement field through the linear superposition of a set of deformation modes whose amplitudes vary along the beam axis. These deformation modes are defined based on the cross-section discretization, corresponding to contour deformations resulted by the imposing of unit displacements on discrete nodes. Then the deformation functions are approximated with nodal displacements through interpolation between adjacent nodes. Applying Hamilton’s principle, the governing equation is derived and further interpolated for the finite element implementation. Numerical examples are also presented to show the accuracy in reproducing dynamic behaviors of thin-walled box girders.