Beam Priority Inconsistent in Section

[Kate_Talbott]

I have recently been experiencing a phenomena where the intersection priority of custom profile beams is not reliable. For example, I have modeled a custom profile for TJI joists, half of them show correctly in section (cutting through the composite slab of my floor structure) and half show as just outlines with the slab hatch visible inside of the beam. Image attached.

I have also experienced the beams looking correct and then randomly changing to be "transparent" during the course of working in the model. This has now become an issue in 2 projects. I would love to figure out how to remedy this.

Operating system used: Mac Intel-based Ventura 13.3.1

 

[Barry Kelly]

If you show just the beams and the floor slab in 3D, then select the slab.

Do you see highlight lines where the beam is cut from the slab?

They can be a little hard to see.

If they are not there, then the beam materials are not cutting the slab.

If they are then the section should be correct.

Does 'Display Order' make any difference?

Barry.

[Kate_Talbott]

Hi Barry - so sorry I did not see your response until now! I just ran into this same issue on another project, and it prompted me to sign in here and check this thread.

If I select the slab and beams in 3D I do indeed see the green cutlines around all of the beams - both the ones that show correctly in section and those that do not.

Display order does not impact how this is seen in section.

I am at a loss and it is making me super frustrated! It happens in wall sections too - my headers are not "cutting" through my insulation despite the LVL header building material having a priority setting of 950 while the insulation material is at 200.

[Barry Kelly]

Don't select the beams and the slab at the same time (see my image - the 2 beams on the left are not cutting the slab).

Select just the slab and look to see if you can see the hole (lines) for where the beams are.

If the beams are creating a hole in the slab in 3D (you can see the outline of the beam when you select just the slab), then you would expect that the cross-section would display correctly with the slab not showing where the beam is.

Can you copy the affected slabs and beams to an new empty file?

Does the problem still exist there?

If so, attach the file here and I will have a look.

Barry.

[Kate_Talbott]

Good morning Barry - thanks for the follow-up reply. When I select the slab I do not see the lines of the custom profile beams - so that seems to be the problem, but I am not sure how to resolve that. 

The slab is a composite - the bottom layer of the slab is "insulation" with a material priority of 100.

The custom profile TJI beams are made up of 2 materials - each with a priority of over 700.

The TJI beams are on a layer with priority 100

The floor slab is on a layer with priority 4

What am I doing wrong here?

 

[Barry Kelly]

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@Kate_Talbott wrote:

The TJI beams are on a layer with priority 100

The floor slab is on a layer with priority 4

What am I doing wrong here?

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For the beams and slab to intersect automatically, the layers they are in must have the same Intersection Group Number.

Or be in the same layer.

Barry.

[Kate_Talbott]

Thank you! I guess I should have know that! I have revised the layer Intersection Group Numbers and now 99% of my issues are resolved. I still have a few TJI's that are mysteriously not intersecting, but I can't spend time figuring that out now as I am on a deadline. I will look into it further once I get this set out the door.

Thank you again for your help with this 😀

-Kate