Finite element analysis of geometrically non-linear structures using translational variables

A "nite element code for geometrically non-linear structures with conservative one-parameter loading is under development. The "nite deformation theory is expressed in displacement gradients and the "nite element approximation for translational variables only is introduced as late as possible. A p-method with hierarchical Legendre polynomial approximation over the elements is used. In order to follow the non-linear equilibrium path an incremental algorithm driven by the dominant displacement component is implemented. A Total Lagrange formulation is applied. Numerical tests on three-dimensional trusses and a plane frame with thin beams are demonstrated