problem retaining wall

[stephanh]

In process of purchase of property. To the front of this place there is a change of (vertical) ground level of approx 1m which has a single skin brick retaining wall. This retaining wall is leaning forward and needs remedial work.
I have a report that the property is some 5m away from an old pond which was back filled in 1928. From what I have seen, the retaining wall would be sat on top of the edge of the old pond.
I am of the opinion that the retaining wall is leaning due to instability in the substrate, ie: the back fill.
Having no real idea of the depth of old pond, I was thinking to use hand held mechanical auger to drill down has far as I was able, at least 2m, to then pour a number of mini piles to support reinforced beam and to then build new retaining wall.
My question is: does this seem feasible - I have never used a mechanical auger - has anyone suffered similar and if so how did you solve?

 

[freddiemercurystwin]

Can you do a sketch of what what?

 

[Ivor Windybottom]

If by single skin you mean one brick width, i.e. 100mm, then it probably doesn't even have a foundation and/or is built on top of topsoil.

In reality it probably just needs a trench down past the topsoil into whatever's beneath, then concrete trenchfill followed by a suitable wall (definitely not single brick). It's only 1m, it doesn't need to be built like a skyscraper. You'd need to dig anyway, you'd be best off just digging first before deciding whether it needs anything special.

 

[Dereekoo]

There could be quite a bit of force behind that wall if its retaining 1 m of soil which could be being pushed over because the founding strata is weak or the foundation is not large enough or the the bond between the brick beds have failed.
A little light reading:-

 

[Ivor Windybottom]

Most often it's because the existing wall is inadequate, as it sounds like is the case here.

It needs a foundation, suitable strength and drainage. Without drainage it's a dam, and is guaranteed to tip or crack unless it's built like a dam.

 

[freddiemercurystwin]

The rule of thumb for a mass retaining wall is the thickness at the base should be about 1/3 of the height. But a sketch would clarify what this pond oddity has to do with things.

 

[noseall]

If by single skin you mean one brick width

1/2 brick width.

 

[stephanh]

OK - I think I might have jumped too soon, I just want to 'hit the ground running' when I get there.
The little light reading has been read, thank you. I would like to say I totally understood it, but no.
Plan now is to dig out until reaching base of existing wall to see if foundation (if any) is adequate, then go deeper if necessary.
Start again might cover the situation.
Thanks for replies

 

[Ivor Windybottom]

1/2 brick width.

It's 1/2 a brick length = 1 brick width!

...but it depends what you call a length or width.

 

[noseall]

It's 1/2 a brick length = 1 brick width!

...but it depends what you call a length or width.

The industry, architect's and builders say a single skin wall is a half brick wide or thick wall.

 

[Ivor Windybottom]

Yes, I was merely attempting to clarify what was meant by single skin, as most mean 100mm, but some think a 225mm wall is a single skin.

But neither is adequate for holding 1m of soil anyway, and it's fallen over, so it definitely needs replacing with something suitable.