Want your retaining walls to stay plumb and square.? It’s not the frost heaving at the base that’s the issue. Hydro Impaction.. When water mixes with soils and creates large amounts of pressure, the water
stayes in the soil and together, they push on the wall.Clear aggregate should always be the first backfill used. It allows the water to drain away from the wall, rather than adding weight to the soil. No heavy mud = no added pressure pushing your wall over.
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