The back of my house slopes down and away about 20 ft. My brickies have put up a nice solid 5 ft retaining wall and now I need to back fill the space left to get the base level for some paving slabs. There are existing slabs from the old patio still in place and a concrete section where an old shed stood. What is the procedure for filling in such a large area (20 ft by 20ft approx) I have tons of clay ,half bricks general rubble sitting around in the garden. Can i mix it all up compact it with whacker then finish with mot 1 and dry mix?
back filling how to ?
- Thread starter slicknick
- Start date
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J
joinerjohn
A nice solid 5ft retaining wall.
How thick is the retaining wall? Can't be single skin to hold the amount of infill your talking about. Have they incorporated drainage holes in the wall?
How thick is the retaining wall? Can't be single skin to hold the amount of infill your talking about. Have they incorporated drainage holes in the wall?
9 inch wall with correct bond and return toward house but no drainage holes as yet although they were discussed! I would have thought that what wth the depth of infill and pointed patio slabs on top of it all water seepage would not be evident?
9" sounds way too thin for a 5ft retaining wall. A crude rule of thumb for mass retaining wall is that the depth at the base should be about 1/4 - 1/3 of the height. Its not been designed has it?
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As i said there is an existing patio area. It has been down for 25 years or so and extends about 15 feet from the back of the house and is solid . I am only filling in the last five or so feet . The reason this work is being done is mainly to level out the slope at he rear of the house that was originally a rockery well more like a dumping ground for the victorian builders rubble! Any way my question was regarding the infill for this project?
I'd ditch the clay, when it gets wet it will swell up and push the wall out..
it will also retain water against the wall and not let it drain properly..
it will also retain water against the wall and not let it drain properly..
In my opinion your wall is an accident waiting to happen.
Have fallen out with more SE than I care to remember, but I takes me hat of to any SE, when it comes to designing a retaining wall. Would never consider building one over metre high without SE drawings.
I can only scratch the surface on retaining wall design, but there aue three positions for a retaining wall. At rest. Active. Passive.
It is the active pressure that rattles them over and without weep holes and drainage, the water pressure will build up and add to the lateral earth pressure and external force.
Anyhow all that is irrelevant, as imo your wall is no where man enough to support 1.500 of fill.
Water will seep into all surrounding ground and find its way down to the lowest point, and that will be bottom of your wall. When you backfill for every lin metre you will be putting in approx 1.5 tonne.
old un
Have fallen out with more SE than I care to remember, but I takes me hat of to any SE, when it comes to designing a retaining wall. Would never consider building one over metre high without SE drawings.
I can only scratch the surface on retaining wall design, but there aue three positions for a retaining wall. At rest. Active. Passive.
It is the active pressure that rattles them over and without weep holes and drainage, the water pressure will build up and add to the lateral earth pressure and external force.
Anyhow all that is irrelevant, as imo your wall is no where man enough to support 1.500 of fill.
Water will seep into all surrounding ground and find its way down to the lowest point, and that will be bottom of your wall. When you backfill for every lin metre you will be putting in approx 1.5 tonne.
old un
1,500 what?
I'm in similar position as slicknick (although my wall's a lot thicker!).
If drain holes are drilled after the wall's built, what size should they be?
Good post.. i go on about the same lines.. below 1m retaining wall and i will rarely even look over the posts on here.. anything over and i'll stick my oar in..
A 215mm thick brick wall is suitable upto about 900mm of retained soil (600x300mm deep footing).. now you can either increase the mass of the brickwork (and maybe the footing size) or simply only backfill so theres 900mm height difference between top and bottom ground levels..
Make sure its well drained
SNM: 1.500 refers to 1.5m.. which is about 2.2t per meter of wall backfill..
50mm dia holes should do.. but you will need some kinda drainage behind the wall so the water is channeled to the weepholes.. normally some pea shingle wrapped in teram along the back and/or a perforated drain pipe..
Static, Thank you. Very pleased you stuck your oar in with a very sensible post, however, had no idea you rowed for a cockless four. Have I spelt that right?
Nick, Static has given you a couple of options to get out of jail, we do, but we do not think you will understand first option.
If you want us to tell you what we would do, then come back, and will be pleased to advise. If you do it yourself, cost yer about £60.00 linear metre.
old un.
Nick, Static has given you a couple of options to get out of jail, we do, but we do not think you will understand first option.
If you want us to tell you what we would do, then come back, and will be pleased to advise. If you do it yourself, cost yer about £60.00 linear metre.
old un.
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