A Simple Retaining Wall Solution
Traditional retaining wall solutions can be expensive and restrictive for example cast-in-situ construction is slow and expensive to build and precast retaining wall panels are restricted in height.
Let’s take a fresh look and see how concrete interlocking blocks or more commonly known as concrete lego blocks can be used as the solution.
They come in various sizes the most common is 600mm x 600mm x 1500mm long and have a mass of 1.1 tonne.
They can be used to build two types of retaining wall.
- Gravity retaining walls
- Reinforced earth retaining walls
Gravity retaining walls can be built up to a height of 4.8m. Above this height the wall becomes expensive and the reinforced earth wall become a better option. Gravity walls rely on the mass of the wall to resist the forces that are trying to push it over, slide it, and overturn it. Walls are normally designed to a factor of safety of 1.5. This means there is 1.5 times the mass than the forces trying to push it over.
Reinforced earth walls are different. Geo mat is used to create a mass of earth that becomes the structural element of the retaining wall. This is done by building the earth wall in layer that have a geo mat between each layer. Geo mat is a plastic layer that has holes in it and has a very good tensile strength.
The concrete block act as a protective facing to the wall and allow the reinforced earth wall be built safely. The geo mat is attached to the blocks with galvanized steel fixing. Reinforced earth walls can be built to 15/20m high and is a very economical solution to high retaining walls. You can read a little more about how we build our retaining walls here
A number of factors are considered when designing a retaining wall. The main considerations are: The material being retained, the height of the water table, the general geographical form of the location, the bearing capacity of the earth the wall is going be sitting on and the height of the wall.
A Simple Retaining Wall Design and Build Guide
We have produced a simple design guide for retaining walls. Click on the image below and download your copy.