Does a geotextile layup exert pressure against a retaining wall??
Even if it doesn't, the fill between the geotextile layup and the wall will exert exactly the same pressure on the wall as if the geotextile layup were not there.
Think of it this way, if I have a 30' vertical piece of 1/2" pipe and fill it with water, the pressure at the bottom will be exactly the same as the water pressure 30' beneath the surface of the largest lake on earth.
No matter how thin the fill layer is, the pressure vs. height relationship is the same. AND, no matter what you do, the fill will always be there. You can either choose what the fill will be by placing it there yourself, or allow it to form from whatever debris is washed out of the geotextile layup, or washed into the space behind the blocks from above. Over time a void behind the wall will always fill up. It is far better to have a material you select than whatever random collection of debris forms naturally.
CurlyDave I'm thinking that the geotextile which is rated at 1400 lbs tension per linear foot.....
will hold back the fill pressure as the textile becomes tensioned.
.....and as the backfill settles to its resting state,
you can imagine removing the bricks and I bet dirt backfill wouldn't fall away.
Like digging a vertical dirt wall, it holds.
It doesn't entomb the gravedigger (usually).
If that was the case all dirt terrain would eventually be "flat".
I guess depending what "eventual" means. Millennia?
I doubt it exerts an "eternal" hydrostatic pressure.
It probably stops eventually, if NOT saturated with water.
Where I live there are steep (dirt) hills that "appear unchanged" year to year.
But OK you can see in my diagram some of the backfill is 5/8 clean, which would fall away, but I can't see it exerting eternal pressure.
I could be wrong.
But agree that rock that drains is the proper material between the sand and the blocks.
Do you have a cross section drawing of the existing geotex you can post?
aircommuter here's my documentation (CAD by photoshop
).
Thx for the image airbiscuit!!!
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Do you have an idea of what your cost is going to be?
Well 170 blocks were $510 plus $75 for homedepot guys = $585
New blocks at the store was $1500 and I didn't even ask what delivery would cost.
I think used blocks could be had for less but these became available at the time that I needed them (now) and I just paid the price.
Geotextile was $400 for a 610ft roll (no pedigree)
drainpipes were $50
20 60lb bags of concrete for the retaining wall supporting the stairs was $100
1/2 yd gravel costs $35 here, I may need another $70yard.
That is $1235 thus far.
There has to be other costs I'm not thinking of.
"Peanuts", you might say....
I dove for the pallets.
Something like twelve?? Or 15? 11yd truckloads of sand were "free" and 11yds of fill dirt for the top.
Hours and hours of my time, my eqpt hours, is "priceless"
The wallbuilder guy (tomorrow) may cost $200-$300 per day and I don't know how long he will take.
My (old) back will be so happy that I'm handing over that cash.
I bet he'll appreciate me handing the blocks down to him with the mini-ex.
And it looks like TBN has provided some free engineering, which is much appreciated.
The cost, compared to the value (if it doesn't cause me any trouble) is peanuts.
The purpose of this construction is to create a car-parking space for this little house that's on a steep hillside.
I'm quite curious what you think market value would be ----> if it went out to bid.
It's substantially more construction than the 55ft wall mentioned a few posts back.
Never heard that before! Love it!
