HouseBoy
Structural
- Nov 21, 2005
- 464
Curious to know what others think about how much does the use of large (4 ft x 4 ft x 8 ft) EPS foam blocks against a tall basement wall.
We have seen this produce used in large highway fill and I'm wondering how much pressure reduction should be expected in a basement wall "backfill" situation.
Say we have a 16 ft tall basement wall on a sloped site. Ordinarily we might design the wall for equivalent fluid pressure of 60 psf per ft depth. Seems that some reduction of the pressure can be achieved by reducing the weight of the soil directly against the wall. It wouldn't change the pressure contributed from the slope but reduction of the overburden force should help.
HOW MUCH DOES IT HELP?
Would it be more helpful to place 8 ft tall x 4 ft wide foam at the top 8 ft or the bottom 8 ft of a 16 ft tall wall (with full height backfill)?
Would it be necessary to place wider amount of foam (wedge shape) such as 8 ft wide at the top and tapering down to 4 ft at the bottom.
Just wondering if something like that would be helpful. Foam is expensive but so is digging out old clay and hauling gravel up a slope.
Thoughts?
We have seen this produce used in large highway fill and I'm wondering how much pressure reduction should be expected in a basement wall "backfill" situation.
Say we have a 16 ft tall basement wall on a sloped site. Ordinarily we might design the wall for equivalent fluid pressure of 60 psf per ft depth. Seems that some reduction of the pressure can be achieved by reducing the weight of the soil directly against the wall. It wouldn't change the pressure contributed from the slope but reduction of the overburden force should help.
HOW MUCH DOES IT HELP?
Would it be more helpful to place 8 ft tall x 4 ft wide foam at the top 8 ft or the bottom 8 ft of a 16 ft tall wall (with full height backfill)?
Would it be necessary to place wider amount of foam (wedge shape) such as 8 ft wide at the top and tapering down to 4 ft at the bottom.
Just wondering if something like that would be helpful. Foam is expensive but so is digging out old clay and hauling gravel up a slope.
Thoughts?