Retaing wall specs

[Elltee]

Im looking to build a 11.2m long x 1.2m high retaining wall.
Of which the top 700 is soil and 500 limestone
Does this sound about right?
Recommended from a 'skilled friend'

6inch/140mm 7n dence block
10mm mortar
8 courses all laid flat
6 courses 440 deep
2 courses 215 deep
Pillars 2 meters apart max
1.5 blocks deep

Foundation 300 x 600

350 blocks not inc pillars
Could I save any blocks/work?
This is one of 4 walls to build

 

[frutbunn]

As a rule of thumb a mass retaining wall width should be a quarter of the being retained.

 

[Elltee]

As a rule of thumb a mass retaining wall width should be a quarter of the being retained.

This does follow that bar the top two courses. The last 300mm would be massive overkill at 440 wide wouldnt it

 

[^woody^]

215 blockwork will be fine

The important things are foundation - suitable depth and width, and drainage at the rear

 

[tony1851]

215 blockwork will be fine

The important things are foundation - suitable depth and width, and drainage at the rear

I think 215 blockwork would be insufficient.

 

[frutbunn]

As a rule of thumb

This does follow that bar the top two courses. The last 300mm would be massive overkill at 440 wide wouldnt it

You can decrease width as the height increases.

 

[Elltee]

As a rule of thumb

You can decrease width as the height increases.

1200/150=8 courses
At which point us considered acceptable to decrease thickness?
4x215 thick = 860 max height
860/150=5.7 courses
So therefore would 5 courses at 215 and 3 at 440 be suffice?

 

[rougharsedbrickie]

Rule of thumb is 1/3 not 1/4

 

[Elltee]

Rule of thumb is 1/3 not 1/4

1200÷3 is still 400 so 440 layed inward or 2x215
What size block and pattern would you use?