How to Correct Frost Heave in Cobblestones
- 1). Scrape out the dirt or sand around the moved cobblestones with a screwdriver. Pry up the cobblestones. Replace any chipped or cracked stones. Set the others aside.
- 2). Scrape the dirt beneath the removed cobblestones. Flatten it to the level of the dirt underneath the surrounding cobblestones. Remove any roots or rocks coming up through the dirt.
- 3). Place a small amount of construction sand over the scraped dirt. Tamp down the sand as compactly as possible between the surrounding cobblestones.
- 4). Place a cobblestone on top of the sand. Make sure it lines up with the surrounding stones. Follow these steps until all of the cobblestones are replaced.
- 5). Tap the cobblestones down into the sand gently bur firmly with the rubber mallet. Make sure they are all level with the surrounding cobblestones. If one is still protruding, repeat the process of removing the stone, leveling the dirt and reapplying sand, until the cobblestone fits properly into the opening.
- 6). Spread a thin layer of construction sand over the replaced cobblestones. Sweep the sand into the cracks between each of the cobblestones. Make sure they are filled completely; if necessary, apply more sand.
- 7). Spray the cobblestones lightly with water. This helps to pack down the sand and clean any remaining dirt off of the cobblestones.
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