Steel Frame Structure
Model to Download
The most common cause of unstable models are failing member nonlinearities such as tension members.
The following model of a frame, whose columns are simply supported at the base point and have moment releases at the column head, serves as an example.
However, if it is loaded vertically, both tension members fail and the system becomes unstable, which causes a calculation error. You can avoid such an error by selecting the exceptional handling of failing members under ‘Calculate’ → ‘Calculation Parameters’ → ‘Global Calculation Parameters’.
Model Used in
- Useful Tools for Fast Generation of Structures in RFEM
- Useful Tools for Fast Generation of Structures in RSTAB
The most common cause of unstable models are failing member nonlinearities such as tension members. As the simplest example, there is a frame with supports on the column footing and moment hinges on the column head. This unstable system is stabilized by a cross bracing of tension members. In the case of load combinations with horizontal loads, the system remains stable. However, if it is loaded vertically, both tension members fail and the system becomes unstable, which causes a calculation error. You can avoid this by activating the special treatment of failing members under "Calculation" → "Calculation Parameters" → "Global Calculation Parameters".
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3D-Modell und Foto vom Seilspielgerät „Globe“ (© Screenshot: Dipl.-Des. Heinz Bornemann, Bad Bentheim/© Image: Berliner Seilfabrik)
3D-Modell und Foto einer „Tetragode“ (© Screenshot: Dipl.-Des. Heinz Bornemann, Bad Bentheim/© Image: Berliner Seilfabrik)
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