Question
I am designing a set of members using the equivalent member method in RF‑/STEEL EC3, but the calculation fails. The system is unstable, delivering the message "Non-designable - ER055) Zero value of the critical moment on the segment".What could be the reason?
Answer:
Please check to see if all sets of members selected for the design are straight sets of members. The equivalent member method is only applicable for straight sets of members with a uniform cross-section, so no taper is applicable, for example. In this case, use the preset General Method.
Do you have any questions?
![Deformations as First Result of FEM Calculation](/en/webimage/008929/581233/KB_1571-01-en.png?mw=512&hash=ac2c4fcf777d6d1e5dd5800b86624ba6fd1a1005)
The deformations of the FE nodes are always the first result of an FE calculation. It is possible to calculate strains, internal forces, and stresses based on these deformations and the stiffness of the elements.
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In this article, you will learn how to model a simple end plate connection in RFEM 6.
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Utilizing the Steel Design Add-on, steel design is possible according to the AISC 360-22 standard. The following article will compare the result output when calculating lateral torsional buckling according to Chapter F vs. an Eigenvalue Analysis.
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In the ultimate configuration of the steel joint design, you have the option to modify the limit plastic strain for welds.
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The "Base Plate" component allows you to design base plate connections with cast-in anchors. In this case, plates, welds, anchorages, and steel-concrete interaction are analyzed.
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In the "Edit Section" dialog box, you can display the buckling shapes of the Finite Strip Method (FSM) as a 3D graphic.
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