| Archive for Downsizer For an ethical approach to consumption |
| Mutton |
Using welded mesh on bank - durability and use questionsOut the back of the house we have a very steep bank - really more of a shallow cliff. It leans back from the vertical by maybe 10 degrees, 20 degrees at the most. The local soil and stone is very close packed so it is mostly stable. Mostly, because the front of it is eroded each winter by frosts. Without that happening it would be fine.It is north west facing and while some plants are establishing themselves their roots are not meaty enough to stop the frost erosion. It is about 1.5 meter to the top and 12 meters long. We've looked at building a block work wall - but that would take us months, cost a bit and be ugly. It is also over the top as we don't need a retaining wall as such, just a little bit of cladding. We've looked at dry stone walls but again, time and money. So the current plan is to put the kind of welded mesh used for gabions along the front of it. e.g. http://www.weld-mesh.com/weldmeshsheets.php The plan is to use stainless steel metal pins to pin it into the bank behind. We will then level up between raggedy surface of the bank and the smooth gabion mesh. This is not using it as gabion baskets, but a single sheet, leaning back parallel to the bank and maybe 30cm away from it at most. We will then tip a mixture of stone and soil between the bank and the welded mesh. After that we will do a little bit of ornamental planting and otherwise let all the local plants establish themselves (they do each summer on the bank, then tend to fall off in the winter). So the plan is that with the bank surface supported by the metal mesh, the surface won't erode as it does now, the plants will establish themselves and we will have a firm surface in a few years. Our questions are: What is the life span of welded metal mesh? Does anyone have a preferred supplier? Has anyone tried to do what we are planning? Has anyone got a better solution? We really want to avoid gabion baskets as short on space and on "pure" stone without soil mixed in. |
| troyannick |
Try Fine Mesh, Telford we did some gabions at Lancaster Uni with their gear |
| Bebo |
http://www.terram.com/applications/soil-reinforcement.html
How about a geotextile? |
| Mutton |
Thanks Bebo. Took a look. They say up to 80 degrees from the horizontal and our bank is a bit steeper than that. Also looks from the pictures that
you need a foot or two in front of the bank are handfilling layers/bags - the drawings looked rather neatly layered. If I've got that wrong anyone, please say 
We don't have much space and were also hoping to use a mini digger at the top of the bank, for pushing soil over the edge and hence tipping the soil and stone mix down behind the pinned wire mesh. |
| AlexBy |
It doesn't sound that good and idea to me. You will be relying on pins stuck into the banking to hold it back. "soil nailing" type principle I would say. I am a general civil engineer, not a structural engineer, but it feels wrong |
| Nick |
I bet it'll be very expensive. Could you not chicken wire across the whole face? Nothing large would come though it and roots would hold it in place after a spring growth.
I'd want to overlap the top and peg it down very firmly. I'm not saying your idea is bad, I have no idea, just throwing in another. |
| Bebo |
Thanks Bebo. Took a look. They say up to 80 degrees from the horizontal and our bank is a bit steeper than that. |
90 degrees from horizontal is vertical. You can't be much steeper than 80 degrees (as there are only another 10 degrees to go before its a wall).
What about grading the pitch?
@Bebo - yes had a metric muppet moment and went for 100 degrees being vertical. We are just at the maximum - as in it is at 80 degrees. Will take another look.
@Ty Gwyn - nice thought but don't want to do that as space up the top of the bank is enough for a digger at present, but limited and it is somewhere we wouldn't want to make any smaller. (For complicated reasons that would take a while to explain.)
I'm thinking - welded mesh (as in reinforcing mesh with 4 or 6 inch squares) , set in a shallow footing to hold bottom in place and covered in a finer mesh (e.g. chicken mesh). The heavy mesh will be strong enough to maintain a smooth face without bulging when backfilled and the finer mesh will retain the soil and allow plants to root. As long as the heavy mesh is fixed securely so that it doesn't bulge when backfilled I see no problem.
I would not recommend such a plan to retain a bank, but I feel it would be adequate to retain soil until plants are established.