New
FAQ 002704 EN-US 03/27/2019

Thomas Günthel Design RF-IMP RF-STABILITY RFEM

How can I perform a stability / buckling check on a tensile structure?

Answer

The proof of stability for tensile structures can be converted into a pure stress analysis, if the theory is considered to be 2-fold and the imperfection required by the standard has been applied to the system.

With the help of the modules RF-STABIL and RF-IMP imperfection (resp. a preformed FE mesh). The type of imperfection depends heavily on the component and the standard used. For bars, which were modeled as a tensile structure, the values from DIN EN 1993-1-1: 2005 5.3 can be used. For flat surfaces, for example, the values from DIN EN 1993-1-5: 2006 Appendix C can be used. For trays, the problem is much more complex and there are different approaches. From a generation of imperfections I would advise against this and perform the buckle proof by means of MNA / LBA concept according to DIN EN 1993-1-6, which does not require an approach of imperfection.

If, for example, the surface model of a steel girder is to be detected, you can proceed as follows, for example:

First A burden me comparatively (compared to. other internal forces in the load case) select high normal forces, in most cases the self-weight load case or a load case combination with the corresponding own weight is suitable. It may be necessary to provide each load combination with an individual imperfection.

2. Calculate load combination according to 1-order theory and use as the basis for RF-STABIL

3. Using RF-STABILITY to find the first eigenstate of a global failure

4. Using RF-IMP, use the calculated eigenmode as the basis for an imperfection. In this case, for example, 1/300 of the carrier length can be used as the amplitude.

5. Create a load case combination that uses the generated imperfection as a basis and is calculated according to 2-order theory.

6. Perform a proof of tension on the basis of this load case combination, which at the same time is also proof of stability of the structure.

Keywords

Buckling check Dents Stability analysis Shell Structures Shell buckling Plate buckling 1993-1-1 1993-1-5 1993-1-6

Contact us

Contact Dlubal Software

Did you find your question?
If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

(267) 702-2815

info-us@dlubal.com

RFEM Other
RF-IMP 5.xx

Add-on Module

Generation of equivalent geometric imperfections and pre-deformed initial structures for nonlinear calculations

Price of First License
760.00 USD
RFEM Other
RF-STABILITY 5.xx

Add-on Module

Stability analysis according to the eigenvalue method

Price of First License
1,030.00 USD
RFEM Main Program
RFEM 5.xx

Main Program

Structural engineering software for finite element analysis (FEA) of planar and spatial structural systems consisting of plates, walls, shells, members (beams), solids and contact elements

Price of First License
3,540.00 USD