Structural Framing Justification/Position changes with Cross-Section Rotation, How to keep the position from changing?

[kevin.anggrek]

Using Revit API, I was able to place structural steel beams inside the Revit model. In order to tweak the cross-section rotation of each individual framing members, I set the rotation angle to the BuiltInParameter.STRUCTURAL_BEND_DIR_ANGLE parameter. This approach allows for the beams to rotate around its reference or location line. However, the justification of the member changes with cross-section rotation as seen below:

Original state with no rotation, the beam is on-plane

After rotation, the justification of the beam changes and is no longer on-plane (the depth changes)

The correct justification that I want

I understand that this occurs because the member rotates around its location line as shown in the picture below, thus the justification changes.

In order to fix the justification, I know that the y Justification and z Justification can be set internally since both of them are BuiltInParameters. Setting both y and z Justification will fix this problem However, I am curious whether there is a simpler solution where I can rotate the element but still keeping the element's depth or position on-plane with its original state.

Thanks in advance

[jeremy_tammik]

Afaik, the exact location line position is fixed by the family definition. I would assume that you can tweak the the framing member family definition to place the location line in a position that facilitates the rotation you need. I have also asked the development team for you whether they can suggest any other, simpler approach.

[kevin.anggrek]

Much appreciated sir @jeremy_tammik 

Indeed, modifying the innate location line position of each beam family would let me to rotate the cross-section of the beam in such a way that will meet my requirements. However, this also means that I will need to do this step for different kinds of families.

If I may, comparing with Tekla Structures for example, they define the position of each steel beams using three parameters: On-plane, Depth, and Rotation setting. Both their on-plane and Depth setting is pretty similar to y and z Justification in Revit. However, it is easier in Tekla to set the steel beam so that it is underneath the reference line by setting the Depth parameter to be "BEHIND", by doing it this way, the beam will always be below/behind the reference line no matter how it is rotated. In Revit, we actually have more freedom in determining the location of the rotation axis (by default, the cross-section rotation has its rotation axis set as the location line of the beam), but the justification of the element changes with rotation (e.g., y Justification might first control the left-right justification of a beam but later change to controlling the up-down justification after being rotated 90 degrees). That is why, I am wondering whether Revit has a different or alternative way in rotating elements that will still keep the depth position of each element from changing.

Once again thank you very much for your help in asking the development team!

[jeremy_tammik]

Thank you for your appreciation. I see your point. I have not heard back from them yet.

[RPTHOMAS108]

I don't think there is a way, we always set angles out from corner (back face) as then you can rotate it about the corner through 90 degrees to change between which leg is parallel to TOS, then flip it if you wanted that leg pointing the other way. Same was also true when aligned with BOS. Revit by default uses the centre which is not great for asymmetrical sections like angles and PFC's. You can change the alignment by setting the parameter but I don't know another way.

Tekla was always primarily a fabrication detailing tool whereas regarding steelwork/non-concrete framing Revit is transitioning into one from starting out a design intent tool for those items. Also don't know exactly where Revit fits in relation to Advance Steel, there is a bit of a mishmash sometimes in terms of functionality cross-over.

[kevin.anggrek]

Thank you very much for the reply sir @RPTHOMAS108 

I agree with you, guess the best way for now is to modify the alignment by setting the justification parameters

[autodesk]

i'm strugling with the alignment of my structure bracing.

if i need to use somthing difrent then round bracing i ofcours wated to have my box profile or angel profile to be aligned flat with my roof beam structure. 

you can change the Cross-Section Rotation but then you will get a not a round number.

use the alignment tool is not rotating the structural framing flat to the ref point.

thanks in advance.