There's a lot of information about DIY gabion walls, but none of the applications that I've seen on YouTube and elsewhere talk about gabion walls as retaining walls. I would imagine that a gabion wall acting as a retaining wall would need to be satisfy some special requirements. For example, I can't imagine that a 4'-high X 2'-wide wall would do the job (not wide enough).
So what are some of the things to think about while constructing a retaining gabion wall? In particular:
- Given the height, how wide does it need to be? (I'm aiming for a height of 3'.)
- Do I have to worry about drainage?
- How do I prevent dirt from infiltrating the basket?
- Any implications for the minimum gauge of the wire mesh?
Best Answer
A quick search for "gabion retaining walls" can find you lots of information.
It found me this useful site: https://www.gabion1.com/gabion-retaining-wall-designs/
As to your questions:
3 feet is pretty short for a retaining wall, the site recommends a simple 2:1 ratio, so a 3' wall would need to be at least 18 inches thick. They also recommend slanting the wall slightly into the slope (~10 degrees).
Drainage is important, but depends a lot on location, you can run perforated drain pipe behind the wall to collection points and backfill above and around the pipe with gravel.
The back of the wall should be lined with geotextile fabric, this should also cover your drainage gravel to prevent clogging the drain pipe.
Gauge size is going to depend on how wide your mesh spacing is. Larger spacing is going to need thicker wires. looking at premade gabion boxes selling for 3 foot walls looks like wire size varies from 9 gauge to 4 gauge.