Gabions (rocks in wire cages)

Over the last few years, NSB has noticed the appearance of wire cages filled with rocks (known as "gabions") as a construction material for buildings and in civil engineering - and has been wondering what they are and why they have suddenly started appearing.

Gabion Wall at Nottingham 1

Example of a Gabion abutment

Initially, NSB thought that they were being used for environmental reasons, to allow wildlife to grow and live in all the nooks and crannies between the rocks.

Then NSB thought that they were being used as an anti-grafiiti measure, as it is hard to make a recognisable image when the surface is so irregular.

Turns out that gabions have been used for a long time to stabilize shorelines, stream banks or slopes against erosion. They are also increasingly being used in architectural applications for their "natural" look. Maccaferri, a world leader in the technology comment that :

"The Gabion is, in fact, a peculiar tool. It does not impose itself on the surrounding environment: it perfectly blends into it. A Gabion is almost always filled with natural materials: stones/rocks and, where possible, locally available materials can be used to fill the structure, thereby ensuring that very little is added (and removed) to the surrounding nature....The Gabion, furthermore, “joins” the nature that hosts it: plants and trees can “sink” their roots in the interstices left free by the rock fill, helping to strengthen the overall system. Nature is no longer a passive actor: it is indeed called to “work” in synergy with man-made structures. This is the environmental engineering of the future."

Gabion wall at Nottingham 1

Worth noting that, in the urban environment, its a good idea to ensure that "youths" can't get the stones out through the mesh, as this cautionary tale from Sneinton, Nottingham illustrates.

Update Oct 2017

Saw this rather decorative gabion in Germany recently

Image Sources
Abutment