NONLINEAR FINITE-ELEMENT ANALYSIS OF THIN -WALLED COMPRESSED AND BENTPIECES

A finite element analysis of the ultimate strength of steel thin-walle d beam-columns is discussed in this paper. The numerical model used wa s developed by Akoussah, Beaulieu, and Dhatt and is based on a Lagrang ian formula of thin-walled bars. In this model, the law of multiaxial elastic-plastic behaviour was adopted and incorporated on the section' s surface by Radau or Gauss type points. Case studies were performed i n which different parameters likely to influence the behaviour of beam -columns were used. Corresponding interaction curves were plotted. The results obtained were compared with those of other authors for H sect ions under biaxial bending, for square or rectangular tubular sections under biaxial bending, and for H sections bended in relation to each of the principal axes. The results emphasize the key role played by sh ear stress on the bearing capacity of open section compressed members under bending.