Constrain a Beam to a Beam

[jenniferd]

I really like that you can attach (constrain) a column to a beam. But, I want to do the same with the top of a beam to a bottom of a beam. Attached is a sketch of a canopy I am working on. Some members frame into or sit on top of other members. I have a column attached to the underside of a beam. You can see there are a number of beams sitting on top of that beam that is attached to the column. Those beams are framing into a beam in the middle of the canopy on the other end. My architectural team is having a hard time deciding the final elevation of the canopy. I tried locking a zero dimension in a section view to no avail.

[rmcelvain.103137]

Jennifer,

I'm not sure you can do what you're asking but have you thought of using a canopy level and adjusting the elevations based on that level? Then when the architect determines T/Steel for the canopy all the associated members will adjust with the elevation change.

It's not what you're looking for but I thought I'd toss it out there...

[Paul Andersen]

Hi Jennifer and Rick, I had a similar canopy not too long ago and here are two approaches to consider:

Member Justification Approach:

1) Set the level or Reference plane for the canopy to be a the Top of Steel for the Lower Framing members.

2) Place all of your Steel Framing (upper and lower members) at this defined level or plane.

3) Select all of the upper members and Right Click -> Properties. In the Element Properties dialog set the Vertical Justification (found in the instance parameters area under the Structural Heading) to Bottom.

Member Defined Work Plane approach:

1) Set the level or Reference plane for the canopy to be at the Top of Steel for the upper framing members.

2) Place all of your Steel Framing (upper and lower members) at this defined level or plane.

3) Go to a 3D view and rotate it such that you are looking at the underside of the canopy and have access to the members that need to be lowered.

4) Select all of the members to be loaded and hit the Edit Workplane button on the options bar. In the Work Plane dialog that opens choose the Pick a Plane radio button and hit OK.

5) Hover over the bottom flange of the lowest member until it pre-highlights and then Left Click Select.

All of your lower members are now using the bottom flange of one of your upper members as their workplane. The nice thing about this approach is that not only will the lower members travel with the upper members as their elevation changes but, if the member size of the upper framing member that they are now attached to gets deeper or shallower they will still stay connected. The only thing to watch out for is that your lower framing is always attached to the deepest upper member.

So you don't have to redraw your canopy you can select all of your current members and hit the edit workplane button in the options bar to set them all to a common level or workplane and then follow step 3 of either approach outlined above. The middle member that is at the same top of steel as the upper members will either require you to set an offset from the defined level or use the top flange of the upper framing as a workplane if you want it to travel with the rest.

[rmcelvain.103137]

You remember on the Charlie Brown cartoons when the teacher talks ...... the 1st time I read your post it sounded much like that ..... after 2 more times I think it sank in :) ....

I looked for the "Big Eyes with Jaw Dropped" emoticon but couldn't find it!

Once again Paul, thanks for the insight and for sharing your knowledge - everyone here knows and appreciates your willingness to forward the use of this software. It enables our industry even though we are competing for projects and I can't say it enough - Thank You!

[Paul Andersen]

Thanks for the kind words :Oops: and your insight and participation as well. It never ceases to amaze me the shear volume of information, workarounds, and content people are willing to share to further everyone's knowledge and productivity. These forums are definitely a priceless resource.