Short retaining wall cost
Short retaining wall cost
(OP)
We have a condition where we would like to put in approximately 30 feet (in length) of a 5 foot wide sidewalk. The slope in this condition is approximately 6 in 12, resulting in (approx) a 2.5 foot drop along the sidewalk width. I'm trying to determine the most economical way to retain this small amount of soil. We plan to put in a concrete sidewalk, but a 3' tall, cast in place retaining wall with footing seems like it may be more work (and more expense) then necessary.
Any thoughts? Thanks for your help. (Soil in this area is generally a stiff silty clay.)
Any thoughts? Thanks for your help. (Soil in this area is generally a stiff silty clay.)





RE: Short retaining wall cost
Please see FAQ731-376 by VPL for tips on how to make the best use of Eng-Tips Fora.
RE: Short retaining wall cost
RE: Short retaining wall cost
You note that the drop across the walk is approximately 2.5'. The concrete walk is 4", the drainage course under the walk is usually 6", so the 2'-6" of stiff clay is now about 1'-8". I would look into trenching a 8" - 12" thick x 3' - 4' deep curb along the one side. Form and pour it integral with the walk. Rebar corner bars may be needed to tie the wall and walk together. Whether this is cheaper than the solution offered above is something you will have to check. But, this would limit the work to only having the concrete contractor on the site and one material.
I do admit that the modular block walls do look better and since this is the 90's we engineers should be concerned with aestheics too!
RE: Short retaining wall cost
RE: Short retaining wall cost
Sorry, I guess I used an "old" expression meaning a "sensitive and caring guy" and didn't realize we are in a new century. Maybe it was a "senior moment"?
RE: Short retaining wall cost
RE: Short retaining wall cost
Using a 8" tall by 12" deep modular block, with 28 degree soil (assumed poor) no real load on the wall you should put one course of geogrid (2.75')on top of the second course to be safe. If the soils are better and you have good drainage away from the wall you might get away without grid. Several block systems include mine have a deeper block, 18 to 32 inches. These systems will work with no grid. Basically a true gravity wall structure.
RE: Short retaining wall cost
RE: Short retaining wall cost
RE: Short retaining wall cost
RE: Short retaining wall cost
Please see FAQ731-376 for great suggestions on how to make the best use of Eng-Tips Fora.
RE: Short retaining wall cost