Fitting a curve onto an interlocking block retaining wall can be a difficult task. Retaining walls are intended to be used in areas with hilly lumps, or where the ground is uncertain. This can be particularly awkward where you need to place a retaining wall around a curving garden, or along the edge of a boundary which is curved. When this occurs, you will have to take extra care in placing the wall, and building up the curve from the bricks. Once the main part of the curving call has been built, finishing off the curving ends should not be impossible, so long as you take the work slowly.
Step 1 - Dig the Trench
In order to create your curved retaining wall, you will need to excavate the soil. Mark out an area of ground where you want the retaining wall to be. Place a stake where you want the wall to begin, and then measure carefully until you have reached the extent of the wall. Mark this using a second stake, and then add a curve to the feature by using a string with stakes spread out along the line. You can change the appearance of the wall by increasing or deceasing the depth of the curve marked out. Once you are satisfied with the appearance of the wall, you should then dig a trench, large enough to take two levels of blocks.
Step 2 - Add the Blocks
Once the trench has been dug, level out the ground using your spirit level, and then line with a layer of gravel. This needs only to be about an inch deep. You can then add the first layer of blocks, moving around in a curve. Add three blocks in a straight line, and then leave a gap, and add three more along the line of the trench, repeat for the whole wall. Return and trim down other blocks using the masonry saw until you can fit these in the gaps you have left. Add some more gravel to the bottom of the trench, and then put down your second layer in the same manner.
Step 3 - Add a Retaining Grid
Once you have laid the first two courses of blocks, you will need to reinforce the wall. You may have a reinforcement grid with your wall kit, which will help to keep up the wall. Place the grid against the edge of the block, and roll it out to the ground. Add the third layer above the grid, and stake the latter in place. Add some of the backfill from the trench, plus rocks. Repeat as necessary.
Step 4 - Finishing Touches
As you build the ends of your wall, you will need to take some of the trimming from your fitted stones. If you have half of a block left over, this should be placed onto the end of the wall, and cemented into place.