Surcharge Loads for Retaining Wall Design 2

[oengineer]

I am working on designing a retaining wall adjacent to a 5 story building. I am trying to determine an acceptable surcharge load to use for the retaining wall design.

Does ASCE 7 or IBC provide typical surcharge loads? Is there another technical document that I can find acceptable surcharge load for retaining walls?

Comments/suggestions are appreciated.

 

[JStructsteel]

I would look into AREMA loading for railroads. Thy use the Boussinesq formuulas for loading from a rail onto a wall. Could be adapted to your case.

 

[bridgebuster]

These are unfactored loads from AASHTO LRFD specification. If you don't have AASHTO, You could search online for the Navy Manual, NAFAC 7.02. They would have info also.

 

[Aesur]

You say adjacent to a 5 story building, will your retaining wall and footing undermine the existing buildings footings? If so, you have more issues than surcharge loading, if not, what is the use of the building? Is the building against your retaining wall or offset? If offset, what is the use of the area between the building and your retaining wall? Is there a drive with fire truck access? A sketch of what you have would greatly help with the response.

 

[dik]

What is the loading behind it... for residential/commercial stuff... I generally use a surcharge of 100psf.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[oengineer]

I have seen some surcharge loads of 150 psf & 200 psf. Which of these surcharge loads would be acceptable near a 5 story commercial building for a retaining wall?

 

[Aesur]

As dik said, I typically see 100 psf, however I use 250 psf if fire truck or heavy vehicle access. Please note however, I know nothing about your project, building use, etc. so I cannot say for certain what you should be using. I would look at live load tables in ASCE and IBC to determine loading on floor of the adjacent buildings.

 

[DoubleStud]

Where is the bottom of foundation in relation to the top of retaining wall and how far?

 

[Celt83]

The only appropriate method to determine surcharge from the building involves you doing some form of load take down analysis for the building using either surveyed information or existing structural documents.

 

[dik]

Garbage trucks can exceed the 250psf... just a caution.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[phamENG]

Yeah...it sounds like you're trying to use a 200psf uniform surcharge to account for the presence of a building? Yikes. Absolutely not. To add to what Celt said, you need to determine the foundation type of that building, the location of the foundation relative to the retaining wall, and the load on the foundation. Then you can a) possibly ignore it (or some of it) if on piles and the piles are deep enough, b) apply a strip load surcharge, and c) account for a first floor slab on grade as a uniform surcharge.

But again...if you have an existing building close enough to result in a surcharge...you have bigger problems. How will you prevent the existing building from being undermined during construction of your wall? Temporary sheet piling? Underpinning? If you underpin it, you won't need to account for surcharge.

 

[EngrRC]

Imagine your building foundation is right next to the retaining wall. With this you would use the usual surcharge formula with the building foundation bearing pressure as surcharge load. If it is further apart, the solution will be either a Boussinesq (point load) or parallel strip surcharge load (width B)