Retaining Wall Glossary Columbia MD

The following was sourced from allanblock.com.

Backfill - The soil that is placed behind the drainage material and compacted. Avoid using soft, wet clays or spongy organic soils; these soils do not compact well and will continue to settle after construction.

Base Course - The first course to be installed. It may be totally or partially buried.

Base Material - A base pad of free draining granular material, compacted and level to receive the base course of AB units. Allan Block recommends a well-graded, compactible aggregate, ¼" to _" in. (6.4mm to 19.1mm) diameter, with less than 10% fines.

Buried Block - The block below grade.

Compaction - Good compaction will ensure minor settling after construction. Poor compaction will allow the wall and the materials behind the wall to settle, possible moving the wall out of alignment, bulging or possibly to fail. Proper compaction is very important to wall constuction.

Drainage Material - Free draining granular material used in the block cores and just behind the wall to collect and disperse water. This can be the same material as used for base material.

Exposed Wall Face - The portion of the retaining wall that is above grade.

Gravity Wall - Walls that rely on their own weight and setback to hold up the soil behind them.

Green Walls - Also known as plantable walls. Created by stepping back a course of the block enough to expose the hollow core of the course below, where soil and plants can be placed.

Mechanical Plate Compactor - Mechanical equipment used for compacting soils (available at most rental centers).

Retained Soil - The soil that is held back by the wall.

Reinforced Walls - Walls that require the use of reinforcement grid to add strength and structure to the wall.

Setback - The amount the wall leans back or into the hill.

Soil Reinforcement - A geosynthetic material used for added soil reinforcement behind the wall structure.

Surcharge - An added weight above the wall (driveway, pool, patio) that puts pressure on the wall below.
Tiered Walls - Two or more walls set above or below each other, rather than building one very tall wall. The tiered walls can create more useable space, tame slopes, build raised gardens and give the yard a more aesthetic look.