Stud wall bracing 2

[oengineer]

I have a question regarding stud wall bracing.

I have 12’ high metal stud walls for a building renovation for an indoor Volleyball court. There is no ceiling, the stud walls are partitions and open above to the 24’ plus roof height. Stud walls usually have diagonal bracing at the top to keep them supported laterally and this is usually concealed by a drop ceiling.

The client doesn’t want to see diagonal bracing all over the place going up to 24’ or 30’ high in some places. This would not look good.

Would anyone happen to have any suggestions on how I can specify the walls to have internal x’bracing or something to make them structurally sound from falling over without using diagonal braced studs from the top track of the partitions all the way up to the roof deck?

Any comments/suggestion are appreciated.

 

[jayrod12]

Simpson Strong-tie came up with some moment brackets for the base of CFS studs, however I doubt they'd be capable of 12' tall cantilever studs.

 

[structSU10]

can you put a girt at the top of the wall?

 

[mike20793]

Cantilever tube columns with infilled studs.

 

[oengineer]

@structSU10 - when you say a girt, do you mean like what is shown in the attachment?

http://files.engineering.com/getfile.aspx?folder=6ee4a069-de94-4e81-9994-f9207804d99b&file=girt.pdf

@mike20793 - Could you elaborate more on the Cantilever tube columns with infilled studs. The building is an existing building that we are modifying.

 

[DETstru]

Here's what mike20793 is talking about:

 

[oengineer]

@mike20793 - Would it be possible to do this 12' up all the way to the roof deck?
@DETstru - Thanks for the picture

 

[DETstru]

Here's another option:

 

[oengineer]

@DETstru - So the track or box header acts like a girt? Would it be possible to have 2 rows of this system stacked on top of each other? Would it help add more strength to the bracing system?

 

[DETstru]

Yes the track (or box header) is like a girt. The infill studs' out-of-plane loads react into the track and the track then sends that load into the tall studs. The tall studs send the load into the roof and the slab.

A second track/box header/girt doesn't really help the issue unless you need it based on the distance your infill studs can span. If you're only making them span 12' then you shouldn't need a second row.

 

[oengineer]

@DETstru - Thank you for the suggestion. I misspoke about the roof height. There is no ceiling, the stud walls are partitions and open above to the 24’ plus roof height. It goes 24' to 30' high in some places. If it is 24' or 30', then would a second track/box header/girt be required/helpful?

 

[oengineer]

Does anyone know of any design guides or reference book that also provide information regarding this type of situation?

 

[XR250]

Does anyone know of any design guides or reference book that also provide information regarding this type of situation?

There ain't likely any as it is comes down to a fairly simple analysis. You have plenty of good suggestions here.

 

[jayrod12]

I'm still unclear on the construction intent. In your first post you indicate a 12 ft tall wall, in your last post you make it seem like the studs are going full height.

Which is it?

 

[oengineer]

@jayrod12 - Regarding whether using the 12' height or 24' height, I just spoke to my colleague who is requesting the answer and this is what I was told:

This is for interior stud walls only. They want the sheetrock on the interior stud walls to go up 12’ high. So, these are essentially 12’ high walls/partitions. Even though these studs may be 16” on center, I’m thinking maybe every 3rd stud goes up all the way to the deck (deck is at 24’ plus) to brace the interior wall from lateral moving, because we always specify a certain amount of bracing above the ceiling. In this case though, there is no ceiling.
Alternatively, I was wondering if there is a solution where every 3rd stud doesn’t have to go all the way up to the deck. Is there a method of bracing within the stud wall itself?

 

[jayrod12]

24 ft tall is a big go to only extend every third stud, but that is an option that you could investigate. As someone has already mentioned, you could use hot rolled steel members at a reasonable spacing that went all the way to the roof, then infill between them with standard studs.

 

[oengineer]

@jayrod12 - Thank you for your response.

@Everyone - Thank you all for your suggestions.I will suggest the Cantilever tube columns with infilled studs and the second option from DETstru. I will let them know if they seek to go 24 ft tall then they should use hot rolled tube steel members.

 

[oengineer]

I have a question regarding the stud wall bracing.

Would it be possible to have the 10 ft to 12 ft high stud wall just brace to the existing metal building and it self? Please see attached drawing:

http://files.engineering.com/getfil...le=Alternative_Stud_Wall_Bracing_Solution.pdf

The yellow highlighted portions are the wall and the pink highlighted portions are horizontal braces to be used. The building is an existing pre-engineered metal building.

How would this work as a solution/ What are the potential benefits? What are the potential issues?

Also, here is more information from the Architect:

This is for interior stud walls only. They want the sheetrock on the interior stud walls to go up 12’ high. So, these are essentially 12’ high walls/partitions. Even though these studs may be 16” on center, I’m thinking maybe every 3rd stud goes up all the way to the deck (deck is at 24’ plus) to brace the interior wall from lateral moving, because we always specify a certain amount of bracing above the ceiling. In this case though, there is no ceiling.
Alternatively, I was wondering if there is a solution where every 3rd stud doesn’t have to go all the way up to the deck. Is there a method of bracing within the stud wall itself?

Any comments/suggestion are appreciated.

 

[jayrod12]

I doubt it. On some of the short running walls sure. But you've got some walls there that are over 15 feet long. The girt required at the top of those walls to keep them from being flimsy would be ridiculous.

 

[KootK]

How would this work as a solution/ What are the potential benefits? What are the potential issues?

For better or worse, I've seen a lot of that strategy in interior fit out work. Without a ceiling, the potential issue would be that it's ugly as viewed from below.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.