Howie wrote:

I am about to dig out a section of sloping hillside to make a
garage or carport. I will end up (on the highest side) with a
sheer face of earth approx 10' high and 18' long which I will
need to retain.

This sounds like the sort of job that would be much simpler to pile
before excavating the soil. i.e. you sink a series of adjacent piles to
a depth of say 20' - effectively building a wall with its foundation in
one process while still in the ground. Then you excavate the soil
uncovering the top of the piles on the down hill side. You can then
shutter them and pour concrete to face them neatly. Much less risky than
attempting to retain the soil while digging foundations and building a
wall from blockwork.

As the others have suggested it will need calculations to decide on pile
dimensions etc.




--
Cheers,

John.

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