Analysis of beam cross section response accounting for large strains and plasticity

The nonlinear response of straight, constant cross section of beams is investigated by means of a semi-analytical approach. The three dimensional displacement field is approximated, for a given cross section, using a FE element discretization on the section combined with a Taylor expansion in the beam axial direction. This allows to compute the beam cross section deformation as a function of the stress resultant and moment resultant, without the need to solve a three dimensional model, still allowing to account for complex three-dimensional constitutive laws.