A gravity wall is a coherent structure that relies solely on its mass and geometry to resist earth pressure. Recon blocks are solid wet-cast concrete blocks with large shear keys that create a coherent structure when stacked in a running bond. A 1-inch (2.5cm) setback per course is built in. Recon blocks were designed to create strong and tall gravity walls.
As a rule of thumb, the height of a gravity wall should be no greater than 3 times the base width. Most Recon producers make Recon blocks between 24 inches (30cm) and 84 inches (210cm) deep. Some Recon producers can make even deeper blocks. Based on this rule of thumb, contractors building with Recon blocks are able to build tall gravity walls over 20 feet (6.1 m) tall.
Engineers who are designing Recon gravity walls can vary the size of the block used in the wall, choosing wider blocks at the bottom and narrower blocks on top. Recon calls this a multi-depth gravity wall. At every course, the wall is checked for overturning and other requirements to ensure the wall is safe.