Water can be the most destructive element to a retaining wall. Pressure is dramatically increased when water is allowed to saturate the soil or backfill. Wet soil is heavier and loses its cohesion, which adds pressure to the wall.
To prevent water saturation drainage pathways are added to the site, as well as to the retaining wall to channel water away. These features are one of the most critical steps in designing a wall that will last a lifetime.
The pressures that are applied to the retaining walls increase as external loads are added on top of the wall. When unanticipated loads are added to a wall structure—such as a truck delivering landscape supplies, or a new structure is added on top of an existing wall—the loads increase. Even building a retaining wall with the wrong sized compaction equipment can over-stress a wall. When designing a wall, anticipate and design for future requirements that may affect its performance.
Just like any building project, the foundation must be strong enough to hold the structure. In some cases, removing poor soils will be required before building. In all cases, proper compaction of the foundation soil is required. When excavating on-site soils, be careful to not over excavate. Any soil that is disturbed or not for a foundation, we recommend compaction. Sometimes, you may encounter a previously excavated area that will need to be properly compacted before construction can begin.