Loading Behind Retaining Wall due to Existing Commercial Builds

[CWEngineer]

I am in the process in designing a retaining wall. Currently, there is a one-story commercial building behind this wall.

Is there a standard distance, which if the commercial building is a certain distance away, one can neglect the loading from the existing commercial building on the retaining wall?

Appreciate your help.

 

[JedClampett]

I'd add two foot of soil as a simulated surcharge no matter how far away the building is. If it's close, you'll get the load from the building. If it's far enough away to not get a surcharge, then there's a chance someone will drive a vehicle in the gap.

 

[mikhelson]

To recast your question slightly, you want to ensure that the pressure bulbs of the building and the retaining wall don't overlap. For that you'd need to estimate the width of the building's footings. For the case of shallow footings, the bulb of influence extends to about two-to-five times the width of the footing deep (less for square footing, more for continuous footing) and about two times the width wide.

For a very rough estimate: draw a 1:1 (45 degree) line from bottom of footing closest to your retaining wall and see if it comes close to your retaining wall.

A disclaimer: I'm just a student at the moment, so my experience is limited to textbook examples.

 

[csd72]

I agree with the last 2 posts.

If vehicles could drive at the top then allow at least 100psf forvehicle loads.

If the retaining wall is above the45 degree 'line of influence' from the adjacent footings then it is accepted that it will not recieve significant surcharge loads from the building.

 

[miecz]

For an interesting discussion on retaining wall surcharge pressure, see thread255-150849. My post at the end of that thread was derived from the attached solution, published a long time ago in a book written in Polish that I haven't seen in twenty years.

 

[miecz]

Sorry, I posted the wrong load case. I've reposted the correct case together with my derivation for "the distance to surcharge for no effect on a cantilever." For your case, you'd have to substitute an equivalent surcharge height for your footing bearing pressure.