Page 348 - Masonry and Concrete

Retaining Walls
CHAPTER TITLE 347

units and systems are available, each with a
slightly different method of construction
(Figure 10-3). The units are set back or bat-
tered in each course so that the weight of
the wall leans inward against the soil
embankment. Some types of units interlock
simply by their shape, while others use
pins or dowels to connect successive
courses. Because they are dry-stacked with-
out mortar, interlocking retaining wall sys-
tems are simple and fast to install, and the
stepped-back designs reduce overturning
stresses. Segmental retaining walls are so
simple and so popular, they have virtually
made cantilever retaining walls obsolete.
Unless the look of a concrete, brick, or
stone wall is desired for aesthetic reasons, a
concrete masonry segmental wall is the
fastest and least labor-intensive solution.

10.2 Reinforced Cantilever
Retaining Walls

Some of the primary considerations in
designing and building a cantilever retain-
ing wall should be FIGURE 10-2
Gravity retaining walls.
A stable footing
A dampproof coating on the back of the wall to prevent soil
moisture from saturating the masonry or concrete and eventually
corroding the reinforcing steel or causing efflorescence
Permeable backfill behind the wall to collect soil moisture

Weep holes or drain lines to remove moisture and prevent
hydrostatic pressure buildup

Expansion or control joints to permit natural thermal and mois-
ture movements

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