Steel plasticity with buckling
This example demonstrates computation of a structural detail, where a girder beam crosses a column. A welded pair of U profiles 300 mm creates both cross-sections of the beam and the column. The geometry and the mesh were created in Salome and converted to OOFEM input file via Unv2oofem convertor.
A downloadable zip file contains Salome's hdf file, unv file, OOFEM input file and the control file. Although symmetry could have been used and the problem reduced 8x, the full-scale simulation is carried out to demonstrate symmetric response.
This task contains 10 383 nodes and 30 786 linear tetrahedral elements. Perfectly plastic material is assigned to steel with the yield strength of 200 MPa. Arc-length method with IML solver were employed and the computation in eight loading steps took 11.5 min. Maximum axial force 1.58 MN on the column leads to collapse in plastic/buckling mode. Updated Lagrangian formulation ensured updating nodal position after each time increment thus facilitating second-order theory and equilibrium on deformed shapes assuming small strains in constitutive laws.
Created 01/2011 by Vít Šmilauer. Acknowledgements belong also to B. Patzák, Z. Bittnar, and T. Roubal.