Post-installed anchors into brick

[bridgebuster]

I have a "simple" task: Design anchor bolts to mount a dozen 5' tall camera poles to a concrete coping on top of a brick wall. The project manager doesn't know if there are any drawings of the wall; of course, he didn't measure anything or take photos. Anyway, from Google Street View it looks like the coping is 4" thick; for now I'm assuming the wall is all brick, 3 wythes thick. According to Hilti Profis, I need 2.375" anchors in 2.75" deep holes in the coping. My gut feeling says the coping is just attached with mortar and nothing else, which makes me uneasy. What I would like to do is anchor the coping stone into the brick wall using either option in my sketch but, I can find anything on post-installed anchor design in brick for this situation. I was going to use Appendix D/Chapter 17, with a big grain of salt. Any thoughts?

 

[JAE]

My first thought is that this is a parapet of sorts and any drilled holes in the top of a parapet is bad news. Water migration into the parapet will wreak havoc on the wall long term.

Is there a back-side to the wall where you can anchor into the side of the wall and then extend up the side? That way you are attaching into more "meat" of the wall and not the cap blocks.



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[cliff234]

I agree with JAE for the reasons that he stated. I do not like the idea of bolting to the top of the wall. Mounting to the back of the wall with two anchor points (one near the top of the parapet and one near the bottom) will better resist the wind moment.

 

[masonrygeek]

You should also consider that there may be through-wall flashing under the coping stone and maybe just a dowel pin holding the coping onto the wall below. So don't assume the thickness of the coping in any of your embedment depth calculations. You'll also want to get to know the condition of the brickwork below the coping so you know what you are dealing with. The collar joint between the brick wythes may be non-existent and then you really don't have anything to hold the anchor in place.

 

[MotorCity]

For this sort of application, I'd be inclined to design a saddle (inverted U-shape) that fits over the top of the wall. That way, you engage more of the parapet for resistance instead of relying on the (non-structural) coping. In the applications you are proposing, I would be concerned with water intrusion as mentioned by others and also the top course (or courses) of brick failing at the horizontal mortar joints due to lateral load on the camera pole.

 

[bridgebuster]

Thanks for responses. I did think about the saddle or attaching a bracket by bolting through the wall. Right now, the only camera mounting detail I was given was light pole that would get cut to 5'(the catalog cut calls for 1" dia. anchor bolts). This is a site security project - high-tech cameras, fences, etc. I'm not dealing with engineers.

I forgot one thing: It's not a parapet; it's a free standing wall that looks about 10' tall.

 

[JAE]

For a free standing wall - still would be concerned with water infiltration issues and top-course stability.



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