LTB analysis of pre-stressed steel beams using mono-symmetric thin-walled beam and spatially inclined un-bonded cable elements

Abstract

A FE procedure is proposed for spatial buckling analysis of thin-walled steel beams that are pre-stressed (PS) by spatially inclined cables. Here, the beams are simply supported, and their cross section can be bi/mono-symmetric. Also, the pre-stressing cables are connected to several deviators under bonded/un-bonded conditions. For lateral–torsional buckling (LTB) analysis of the PS beams, a thin-walled beam element for the steel beam and solid beam elements for the deviator members are firstly formulated using total potential energies. After that, the potential energies of two-node bonded and multi-node un-bonded cable elements are rigorously derived, and the corresponding elastic and geometric stiffness matrices are explicitly presented. Finally, the validity and accuracy of the present FE formulation are demonstrated through numerical examples, and a set of parametric studies is conducted to investigate the effects of initial tension, multi-deviators, vertical and lateral eccentricities, and flexible deviators on the LTB of the PS beams.