Steel Joist - Shear Transfer Parallel to Joist

[PEinVA]

I'm looking for a detail at an expansion joint that would allow for movement in the vertical (parallel to the height of the wall) and normal (perpendicular to the height of the wall) directions for steel joist roof deck to a CMU shear wall.

This is a project where we are raising the roof in a strip mall, to match higher adjacent roofs for a new tenant.

The strip mall is split into a series of buildings that have an expansion joint every 220' or so.

The original drawings show a two angles that would allow normal movement only. They don't account for the deflection of the joist. Haven't been able to view if this has worked for the last 25 years, but we'd like to improve on this detail.

I've searched these forums and couldn't find anything that fit my situation.

Any input? Thanks.

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[jike]

I am having a little difficulty following your description. Can you please provide a sketch?

 

[PEinVA]

I'll try later, but hopefully this can help.


I have a joist that runs parallel to a CMU shear wall (warehouse style construction)The building is roughly 220' x 180'.

I have full length CMU walls on either side and need to transfer shear from the deck/joists to the shear wall that runs parallel to the joist.

This joist is approximately 4" from the CMU wall. I have to create some sort of rigid connection that can transfer shear along the length of the wall from the joist/deck, that can allow for deflection of the joist, and horizontal expansion/contraction movement of the wall/deck/joists.

Hope that helps until I can get a sketch up. I'm sure this is fairly common, but not something I've worked with before.

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[DaveAtkins]

You can use vertical slotted holes in the vertical leg of an angle which is fastened with chemical anchors to the CMU wall (not expansion anchors, because you want the nuts to be finger tight). The horizontal leg of the angle is welded to the top of the joist.

But I don't know how you would allow for movement perpendicular to the joist and still transfer diaphragm shear into the CMU.

DaveAtkins

 

[PEinVA]

Dave,
Thanks.

I'm looking to transfer shear in the length of the joist, which is 4-5" from the edge of the wall.

I'll try to get my section up later.

Thanks again.

Rick

RC
All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke

 

[Catacus]

I have seen round steel rods used in similar situations, needs minimum of 2 rods since they are tension only. The rods are parallel with the joist and wall and one end is connected to the wall the other to the joist. Sort of like mooring a boat to a dock. Allows building expansion and vertical defelction of joist relative to wall. Anchorage of the rod to the wall would be the key here.

 

[efsinc]

I am assuming you're in the midst of a tenant improvement project and that the joist is existing and the wall is new because i can't imagine why a steel joist would be only 4 or 5 inches from a parallel wall.

That being, said, can you remove the steel joist and justify the metal deck to span an additional 4 or 5 inches to the cmu wall? then, of course, you have removed 1 of the 2 directions from the puzzle.

 

[hokie66]

RC,
Of the three directions, I think the vertical is the least important. Let the vertical load go onto the wall if it wants to, but you don't have to take the joist out as efsinc suggested.