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003440
2021-07-27

Check of Sets of Members for Equivalent Member Method

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.

Set of Members with Buckling, not Straight
Set of Members with Buckling, not Straight
Equivalent Member Method and General Method (Default)
Equivalent Member Method and General Method (Default)
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