Vehicle Surcharge on Basement Walls
Vehicle Surcharge on Basement Walls
(OP)
For generic basement wall design, I've encountered three design philosophies regarding vehicle surcharge:
1) None at all unless there's a traffic surface nearby.
2) 50 psf so that folks could park cars on the lawn without having their basements collapse.
3) 250 psf so that a fire truck could pull up beside the house if necessary.
Three seems pretty punitive although it feels peculiar to suggest that fire truck couldn't pull up beside the house should the need arise.
What do others do in this regard? Can we safely assume that all fires will be fought from the street?
1) None at all unless there's a traffic surface nearby.
2) 50 psf so that folks could park cars on the lawn without having their basements collapse.
3) 250 psf so that a fire truck could pull up beside the house if necessary.
Three seems pretty punitive although it feels peculiar to suggest that fire truck couldn't pull up beside the house should the need arise.
What do others do in this regard? Can we safely assume that all fires will be fought from the street?
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.






RE: Vehicle Surcharge on Basement Walls
RE: Vehicle Surcharge on Basement Walls
If you look up ACI 332, which is the bare bare minimum for residential concrete, they don't add a surcharge. It's not like you see these things failing all over the place. I think it is reasonable. A car surcharge would easily be distributed over a longer section of the wall.
The thing you should be concerned about it how to brace the top of the basement wall from kicking in. Standard IRC details are kind of a joke. How much lateral restraint should you have at the top of a wall? 250 plf or so? IRC standard details only require a 1/2" bolt at 6' o.c. At one point they fixed the code, then they unfixed it. I don't design it that way, but plenty of people do and can get away with it per code.
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RE: Vehicle Surcharge on Basement Walls
Often your soil pressure can overtake that surcharge pressure by the 4 ft depth. In the end it only increases your total loads by a small portion.
RE: Vehicle Surcharge on Basement Walls
RE: Vehicle Surcharge on Basement Walls
In commercial construction I have had arguments with other engineers in the past. I typically try to accommodate an additional 100psf next to the building to allow for equipment during construction and while in service. I know other engineers who do not provide any additional load. I think, depending on the type of project, this falls under engineering judgment.
RE: Vehicle Surcharge on Basement Walls
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Vehicle Surcharge on Basement Walls
Residential usually 50psf min.
Comercial usually 100psf unless near a road or some other type of pavement then 250psf. Although in most cases 250psf is easy enough to achieve.
EIT
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