Building with Allan Block
Reinforced Patterned Walls
Walls can be built with just one block shape or with many to create beautiful patterned walls. In this example, we are building a two-course pattern reinforced wall.
Using geogrid is the easiest way to add support to a wall. Most geogrids typically come in large rolls and in a variety of strength. These geogrid types are strongest along the roller machine direction and are cut to length. They are best suited for walls over six feet high. AB Reinforcement Grid is designed for walls up to six feet high. It comes in three and four foot rolls and is biaxial which means it has the same strength in both directions and can be simply rolled out along the wall. AB Reinforcement Grid will be needed on every two course pattern to the top of the wall. Check the approved plans and specifications for details.
The base course of block should always be full-sized blocks. Once the base course is completed, begin installing the first layer of AB Reinforcement Grid by placing the edge of the grid against the back of the raise front lip and rolling it out along the wall. Stack the first course of the pattern on top of the grid. Running bond is ideal for offsetting the vertical seams. If running bond is not possible, offset them by at least a quarter of a block and set them flushed against the front edge of the blocks below.
Once the first course of the pattern is in place, sight down the wall to make sure the wall is straight. Adjust the blocks as necessary. Then pull back on the grid to remove any slack. If necessary, stick it in place. Never drive or compact directly on the reinforcement grid. This will damage the grid.
Fill the hollow course in 12 inches behind the block with wall rock. Use a flat-nosed shovel to remove the excess wall rock from the top of the block. After each course, compact the wall rock inside the block course by tamping it in place with the end of a shovel. Then sweep clean with a broom.
Install the next course of the pattern. Build the block course in 12 inches behind the block with wall rock and backfill behind the wall rock using approved on-site soils. Use a flat-nosed shovel to remove the excess wall rock from the top of the block. After each course, compact the wall rock inside the block course by tamping it in place with the end of a shovel. Rake the backfill area smooth to prepare for compacting. Then continue compacting the wall rock in a path parallel to the wall working from the back of the block to the back of the backfill area making a minimum of two passes with a mechanical plate compactor.
Remember to keep all heavy equipment at least three feet away from the back of the blocks and always compact in eight-inch lifts or less. Remove any excess material from the top surface of the blocks by sweeping the block clean with a broom. This prepares a smooth surface for placement of the next course. Continue these steps to the top of your wall.
Place the next course of blocks in the pattern, sight down the wall to check for alignment. Fill with wall rock and backfill with on-site soils. Then compact on top of the block and behind the wall making a minimum of two passes with a mechanical plate compactor. Then sweep the blocks clean. Add AB Reinforcement Grid on every two-course pattern or as specified on the approved plans. Then repeat these steps for any additional courses to the top of your wall.
To enhance your project, view the other building options or visit us at allanblock.com.