International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

This paper presents the buckling analysis of functionally graded (FG) beams. To solve diff erential buckling equations of diff erent FG sections the Rayleigh-Ritz method is used. The FG material is supposed to vary continuously over the beam depth according to power low. A set of analytical evaluation is run in order to calculate critical buckling loads in dependents of material power low index. The accuracy of method is confirmed comparing the results with the finite element ones.

Paper deals with finite element buckling analysis of shear deformable beam-type structures. Displacements and rotations are allowed to be large but strains are assumed to be small. The corresponding equilibrium equations are formulated in the framework of co- rotational description, using the virtual work principle. Displacements and rotations are allowed to be large while strains are assumed to be small. Linear shape functions are used for the axial displacement, while cubic shape functions are employed for transverse displacements and angle of twist. The algorithm is validated on test examples.

This paper presents creep buckling finite element modeling of steel beam-type structure. For beams under sustained loads the loss of stability may occur during a period of exploitation of structure even for loads lower than critical buckling load. For that reason stability is characterized by critical buckling time instead the critical buckling load. The simulation is performed using four nodded Kirchoff- Love theory based shell finite elements. For a space frame, as the test example, critical buckling times are calculated for different levels of applied load, temperature conditions and steel chemical composition.