Swiss Cheese Walls

[skeletron]

There was a post recently where someone commented that a wall was being turned into swiss cheese (or something to that effect). That one had me laughing, but also thinking...

For a retrofit of a typical wall (eg. 6-8" thick with #5 rebar vert/horiz @ 12") with equipment anchored off the wall, are the concrete design checks similar to that as for a slab:
1. Check the bending moment
2. Check the shear
3. Check the bearing

...or are there additional effects that need to be verified? Is there a proximity effect for multiple attachments to the wall? When does your wall configuration change from gouda to swiss cheese?

Recently someone commented that an FEM approach was needed, but for the load level it doesn't seem necessary.

 

[KootK]

...or are there additional effects that need to be verified?

I'd say that the big, additional effect would be consideration of compression buckling. Other than that, quite like slab design as you said.

Is there a proximity effect for multiple attachments to the wall?

Certainly. And a fair bit of judgment would go into the treatment of that as you're not likely to find much formal guidance.

 

[spats]

Since you're saying this is a retrofit, I assume the walls are not load bearing. If load bearing, the axial load creates significant additional bending moments, due to the deflected shape. However, even the wall self weight itself will slightly magnify the bending. See the design provisions for slender walls in ACI 318, Section 14.8.