Masonry to Steel Beam Anchor.

[SteelPE]

I am in the middle of working on a new building that is a single-story structure with a steel frame, a masonry skin and internal cranes. The masonry is not load bearing and we would like to isolate the masonry from taking any lateral loads in the plain of the wall.

I am wondering what type of anchor you would use for such an instance (where you need to take wind loads perpendicular to the wall but don’t want gravity loads or lateral load in the plain of the wall)? I seem to remember a strap anchor, but the were never sufficient to support the perimeter CC loading of ASCE-7.

 

[spieng89]

I don't know how you would isolate the wall completely. Why don't you use clip angles (couple inches wide) spaced for what you need to brace cmu wall against out of plane wind forces. The clip angles would be welded to steel beam framing and then vertical slot connection at cmu wall to not place gravity loading into the wall. Sure that connection would take some in plane loading, but for single-story it'd be minimal and wherever you have braced frames would be stiffer than that clip angle connection anyways.

 

[Coty]

I think what you are describing would be perfect for simple masonry ties, like what you would have with clay brick veneer. Weld those to the roof deck edge angle or steel beam above. Allows slip in plane of the wall and vertical deflection of the steel beam, but transfers out of plane load to the deck diaphragm. Those would have to be some seriously heavy duty ties, though...

 

[WARose]

I think the slotted connection another poster suggested is a good idea. If the steel building is completely braced, it may not try to put much into the masonry (as a shear wall) in the first place.

 

[Deker]

How about something like this:

 

[North2South]

I would do something similar to Deker but use an angle with a taller leg and use oversized or long slotted bolt holes.

 

[bkal]

Is this an option:
Link

 

[SteelPE]

This thread is in conjunction with the an earlier thread which can be found here:

https://www.eng-tips.com/viewthread.cfm?qid=449279

I was trying to avoid the typical angle/bent plate-expansion bolt detail. I was wondering if anyone had anything better.

I just finished up calculating the wind load, and by what I can figure we are dealing with an allowable load of around 25 psf for these anchors (depending on the tributary area). The masonry wall is 20' tall, so we are talking 250-300 plf depending on the attachment point.

I have looked into the h&B anchors in the past and have been disappointed with their capacity (failure loads of 400-500#). By the time you get done applying your FOS your capacity isn't much and you need those things at 8" o.c. and then they are not practical.