A lot has changed in how we build, and the materials we use for, retaining walls.
Retaining Walls – From Then to Now
Depending on your age, you may well remember when retaining walls were built using rocks and even bluestone. In fact, older parts of Australia still have many rock and bluestone retaining walls in place.
Rock walls are typically built at a backward-facing angle, enabling the rocks to withstand more pressure from the soil they are retaining. In contrast, retaining walls made from timber are usually built vertically, with timber posts inserted into the ground and retaining wall sleepers attached to the posts with large bolts.
Over time, however, the significant load pressure from the soil pushed the timber posts over and the wall eventually needed complete replacement.
Then came the use of steel posts, using C channels and H channels, into which sleepers can be slid.
These are increasingly used today, the sleepers commonly being timber, concrete and, now, steel.
Advantages of Steel Retaining Wall Sleepers
A fully steel retaining wall, including steel posts and steel retaining wall sleepers, is much stronger and lighter than other types of retaining walls. Once the posts are installed, they are also much easier to build, with the lightweight sleepers just slipping into the C and H channels.
And Now – Corten Retaining Walls
Today, in addition to standard steel retaining wall sleepers, Corten retaining walls are also available.
Corten retaining walls are made from ‘Corten steel’ – a specific type of steel that comes with an already-rusted look. This brings it a unique appearance that is ideal for situations where something a little bit different is desired.
You don’t need to wait for your retaining wall to rust naturally – the use of copper, chromium and phosphorous when the steel is produced means that it already has its rusted look when you purchase the posts and sleepers.
Where Are Corten Retaining Walls Ideal?
In addition to areas where a unique rustic appearance is sought, Corten retaining walls are ideal for areas where the wall will face higher-than-normal pressures and exposure to salt.
This is because Corten steel is more resistant to corrosion than other types of retaining wall steel. This makes it ideal for areas that are exposed to more water or salt than usual, such as in flood-prone areas, areas with poorly-draining heavy clay soils and in coastal climates where the salty ocean air may otherwise cause problems.