Dry Rock Retaining Wall
Is there a question in here?
Retaining walls in municipalities often require an engineer's stamp
Here it is required at 4 feet.
Manufactured "Garden wall " blocks are not recommended above 2 feet.
Manufactured block similar to Keystone block are about 70 - 80 # each
with some system designed to interlock the blocks.
Concrete walls are designed to resist roll over by brute strength
provided by the footing or mass. It would still be normal to provide
drainage at the bottom of the wall to reduce the hydrostatic pressure
Manufactured walls are designed to leak. It would still be normal to
provide gravel drainage behind and under the wall to reduce hydrostatic
pressure.
Your dry stack stone wall will need to meet the same requirements. The
stones will need to be quite large, interlocked, and well drained with
sufficient mass to resist the pressure of the dirt in a semi-liquid
state during rainy weather.
I hope this helped.
Keep the whole world singing. . .
Dan G
(remove the 7)
"RedHeadAllDay" wrote in message
...
I live in Maine at the top of a hill along the Kennebec River... The
lawn on
the south side of the house slopes gently toward the river, and
abruptly
terminates where the driveway goes up to the house... This poor lawn
is in
the shade 95% of the time, is poor soil (including diggings from a
project
that was done prior to my buying the house), and as a result doesn't
have
much grass and an overabundance of moss... There is a quaint brick
walk that
runs from the front door to concrete steps down to the drive (the
steps are
in the middle of the drive)... In recent years (I inherited all the
previously cited items) there has been some erosion in the soil next
to the
driveway, particularly where the walk meets the steps (with the loss
of
three or four courses of brick)... Other than this runoff, which has
occurred on the sharp slope from the lawn to the drive, the soil is
quite
stable....
My wife, bless her heart, had decided she could no longer live with
the
mossy walkway, and dug it up in order to restore it... I had wanted to
consider this particular project for a bit longer (about 10-20 years
or so),
but now I'm kinda forced into action...
I want to build a dry retaining wall of field stone around the top of
the
steps, then taper the wall along the drive in either direction... I
have an
OLD rock wall in the pasture behind the house that marked a former
boundary
line (the line has since moved, now marked by a row of trees)... I
plan to
use the stone from this wall in this project... After the wall is in
place,
I can put good soil on the lawn and reseed with the appropriate
grass....
These steps are about four feet high at the top, this four foot height
the
wall will need will taper to about three feet high at the street, and
taper
to nothing as you come up the drive to the garage...
I've done plumbing, carpentry, roofing, flooring, and concrete
projects... I
have never done anything with rock, so I have a bunch of doubts in my
head
and would like to save as much of my back as possible.... I know I
need a
batter of 2 inches per foot of height, I plan to put about eight
inches of
crushed rock in a trench at the base of the wall, I expect the wall to
be
about 24 inches wide, made of field stone... I plan to backfill the
wall
with topsoil to the level of the lawn....
Since this is dry, with no mortar, I don't expect to put any drainage
pipes
into the wall...
If anyone has any experience with such a project, and would care to
inform
me of the evil unknowns I'm about to encounter, I'd certainly
appreciate any
comments and advice....
I'll post pictures as this project progresses... I'd like to be done
before
the snow flies....
Bob Curry
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