Retaining wall cross-section — base, buried course, batter, drainage gravel, and pipe
Most of a retaining wall is hidden: a compacted stone base with the first course buried, blocks that step back (batter), a drainage-gravel chimney with filter fabric, and a perforated pipe at the base that daylights the water out.
What this diagram shows
A section through a segmental retaining wall. A compacted crushed-stone base is set below grade and the first course of blocks is buried below grade for embedment. The block courses step back as they rise, giving the wall its batter so it leans into the slope. Behind the blocks is a chimney of free-draining gravel, with filter fabric separating the gravel from the retained soil, and a perforated drain pipe at the base that daylights the water out the front. Most of a retaining wall is below grade and behind the face, not the blocks you see.
Retaining Wall Calculator
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