Thin-walled closed box beam element for static and dynamic analysis

A new displacement-based nite element is developed for thin-walled box beams. Unlike the existing elements, dealing with either static problems alone or dynamic problems only with the additional consideration of warping, the present element is useful for both static and dynamic analyses with the consideration of coupled deformation of torsion, warping and distortion. We propose to use a statically admissible in-plane displacement eld for the element sti ness matrix and a kinematically compatible displacement eld for the mass matrix so that the present element is useful for a wide range of beam width-to-height ratios. The axial variation of cross-sectional deformation measures is approximated by C0 continuous interpolation functions. Numerical examples are considered to con rm the validity of the present element.