Answer:
The lateral-torsional buckling (LTB) phenomenon in general is limited to the major axis bending. For uncommon cases where minor axis bending is a concern, the code does not provide standard formulas to handle such cases.
It is currently not possible to check LTB for the minor axis bending in RFEM. This is something that we may consider implementing in the future.
- For section with Iz > Iy and bending about the z-axis (Member 1), “non-designable” error is listed.
- For sections with Iz > Iy and no bending about the z-axis (Member 2), there is no need to check for LTB.
- For sections with Iz < Iy (Member 3), LTB check is provided according to the selected standard.
