Retaining wall crack, solution to fix please!
Retaining wall crack, solution to fix please!
(OP)
I am in the process of investigating a retaining wall. It is a shape of \___ The short side (the diagonal) is about 10' long and the long side is around 26' long. It is a 6' tall wall (meansure from the top of footing). The wall is a drive way retaining wall, so the back side is only 5.5 ft back fill with concrete slab on the top. It was built up using only 8" CMU blocks with #4 @ 24 "o.c. Footing was around 3'-0". The building built it without any design.
There were two vertical crack in this wall. First one occur @ the joint where the diagonal meet the horizontal. The other crack occur @ 2 ft from the right end of the horizontal wall. These two crack are both veritcal crack and from top to bottom.
The Builder was seeking soultion to fix the wall in order to get the CO. I had suggested him to use the wall anchor to tie the wall back, but the company charge him 6500 for 5 anchor. So, he was seeking another economical solution.
I am thinking building up some buttress behind the wall.
How do I design an adequate buttree to support the wall?
and any other solutions?
Thank you!
There were two vertical crack in this wall. First one occur @ the joint where the diagonal meet the horizontal. The other crack occur @ 2 ft from the right end of the horizontal wall. These two crack are both veritcal crack and from top to bottom.
The Builder was seeking soultion to fix the wall in order to get the CO. I had suggested him to use the wall anchor to tie the wall back, but the company charge him 6500 for 5 anchor. So, he was seeking another economical solution.
I am thinking building up some buttress behind the wall.
How do I design an adequate buttree to support the wall?
and any other solutions?
Thank you!





RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
in my opinion, backfill placement and drainage are about 50%+ of a free standing cast in place concrete retaining wall functioning "properly". foundation is probably 40%, backfill say 50% and wall itself about 10%...let's not forget the contractor that can easily add another 50% to my figures above since they are quite often capable of screwing up almost anything.
RE: Retaining wall crack, solution to fix please!
I don't argue with proper placement of backfill, but in my experience retaining walls fail due to inadequate design and/or construction of the footing and wall. Building an inadequate wall and then trying to rectify it by tweaking the backfill is not the answer.
RE: Retaining wall crack, solution to fix please!
and building anything inadequate and trying to psuedo-fix it after the fact is just silly in my opinion. it costs many times more to "fix it" (usuallly doesn't solve the problem, just extends the amount of time until someone has to "fix it" again) than to just do it correct the first time.
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
if it's a permitting issue, sometimes making the wall under a certain height lessens the requirements for a CO. if it requires a stamp, i wouldn't stamp it unless i designed it and oversaw construction and testing.
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
I'd sit back and re-evaluate what this wall has to do and if it is just appearances, maybe some agreement for accepting a wall that does not look perfect.
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
Be careful in placing the concrete or stabilised sand. I wouldn't go more than about a foot in a lift. If concrete, wait until it achieves initial set (you should be able to walk on it). If stabilised sand, I would require a day in between lifts.
The vertical cracks in the blockwork will still be there, but you may be able to conceal them satisfactorily.
RE: Retaining wall crack, solution to fix please!
Use wire mesh facings and wrapped geogrids or geoynthetic sheets. While some codes require 8' minimum geogrid lengths, you can get it to work with 6' lengths. It's pretty easy to design and will cost about $8 / s.f.
When construction of the wire faced wall is complete fill the void with single size rounded 5-10mm gravel.
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
RE: Retaining wall crack, solution to fix please!
from USACE EM 1110-2-2502 pg 6-16