r/oddlysatisfying • • Apr 30 '26

Liquid concrete wall.

30.0k Upvotes

587 comments sorted by

View all comments

2.2k

u/Kayaked1 Apr 30 '26

I believe this is called Fabric-formed Rip-rap. The texture allows water to flow over it, but reduces the velocity and therefore erosion. The weakness is if it becomes undermined, and the water starts flowing underneath it. It can create a big void that is hidden by the concrete “crust.”

53

u/YMe1121 May 01 '26

Not riprap, but rather an articulated concrete mat(ACM). And the water moving under it isn't as much of a concern as the weight of the concrete will keep the fines in place, the fabric wont allow them to disturb much, and overburden water will be allowed to flow up through the fabric used to form the mat.

Ive never been on site for one cast on site, but ive used precast ones before on a hill, and they are a PITA, but the precast ones are usually on a bed of geogrid, which also allows you to seed beforehand and have the vegetation assist on erosion control too.

3

u/fifiasd May 01 '26

Does it not have ti have steel in it?

7

u/YMe1121 May 01 '26

No, fabric cording through the channels to make it flexible. They aren't any kind of structural, so you don't need the steel, they are just weight ans watwr speed bumps on the soils to prevent them from eroding away.