Question
What does the warning “Cannot assign pushover hinge when wall elements assigned with identical wall ID do not align in a straight line or local axes are different” mean in MIDAS Gen?
[Error] Cannot assign pushover hinge when wall elements assigned with identical wall ID do not align in a straight line or local axes are different.
Answer
This warning appears during pushover analysis when the software attempts to assign a pushover hinge to a group of wall elements that share the same Wall ID, but the elements do not satisfy the required geometric conditions for grouping.
Cause of the Warning
MIDAS Gen enables assignment of a common pushover hinge to multiple wall elements grouped under the same Wall ID. However, for this to work properly:
- All elements must align in a straight line (i.e., their centerlines must be colinear in elevation or plan).
- All elements must have identical local axes (i.e., same orientation/direction of local coordinate systems).
If one or more wall elements are offset, stepped, non-aligned, or have different local axis orientations, the program does not allow a unified hinge assignment and displays this warning.
How to Resolve the Issue
1. Ensure Geometric Alignment
- Confirm that wall elements under the same Wall ID form a straight line in 2D or 3D space.
2. Check and Unify Local Axes
- Make sure all wall elements have consistent local axis directions.
- If local axes differ due to mirroring or rotation, reorient them to match.
3. Split into Segments with Separate Wall IDs
- For walls with bends, kinks, or stepped profiles, assign distinct Wall IDs to each segment that is straight and aligned.
- This allows hinges to be applied only to geometrically compatible segments.
4. Reassign Wall IDs as Needed
- Revisit the wall ID assignments in your model and group only those elements that meet both the alignment and local axis criteria.