Some manufacturers use pins to align the blocks in their segmental retaining walls. Versa-Lok’s pin system ensures that each course has a 3/4-inch setback, giving the wall face an angle of about 7 degrees away from vertical.
In Lock Load’s retaining wall system, face pieces are attached to separate anchoring components called counterforts.
The counterforts work like geogrid fabric, anchoring each panel to the soil mass behind the wall.
While construction details vary, all segmental retaining walls require a well-compacted gravel base and good drainage, and geogrid is often used to reinforce the wall assembly. Engineering is usually required for walls taller than 4 feet or in poor soils.
Segmental retaining walls don’t require a concrete footing but do require a solid base of compacted crushed rock.
Some manufacturers recommend adding a layer of coarse sand to make leveling the first course of block easier.
Synthetic geogrid is used when retaining walls are built on soils containing a lot of silt or clay, or when wall heights exceed 4 feet.
The geogrid reinforces the soil mass behind the wall and helps anchor the block courses in place.
The first segmental retaining wall you build likely won’t look like this, but the photo illustrates the design possibilities offered by these versatile systems, including curved walls and planting areas.
Segmental retaining walls can be used to create planting areas on a steep slope.
Blending segmental retaining walls and hardscape with a deck expands design options.