Untersuchungen zum Nachweis der Stabilität aus der Ebene auf einheitlicher Grundlage

Investigations on the verification of out of plane stability on a generalised basis.

The general method for the verification of flexural and lateral torsional buckling is an interesting alternative to ordinary checking procedures with substitute beams and coefficients. By introducing a design point relevant for the verification, the method becomes more precise. It then leads to same results as a non-linear calculation with an imperfection shape that is affine to the critical shape, the curvature amplitude of which is scaled to the Euler buckling column. By that the method is fully mechanically justified. By considering St. Venant torsion, it is also transferrable to lateral torsional buckling problems. Within this paper the lateral torsional buckling check using the general method is shown and illustrated by means of an example. Furthermore, first results of a test series on lateral torsional buckling of beams with variable moment shapes are presented. Clear boundary conditions and a load direction that remains vertical throughout the whole course of a bending test with lateral torsional buckling required a new test setup and control of the lateral shift of the hydraulic jack.