This latter condition may occur naturally at walls that are not totally freestanding—for
example, at the junction of the wingwall at bridge abutments—or the condition may
occur by design. Examples include locations where the lateral deflection cannot be
tolerated because it retains a structure, or a heavily reinforced concrete counterfort
wall, which is sensitive to settlement, located on material susceptible to settlement,
especially differential settlement. In the latter case the designer must evaluate options
that may include, depending upon the depth of the material that will settle, (1) removal
and replacement, (2) deep foundations to adequate bearing material, or (3) selection of
a different wall type, if conditions permit, that will be more tolerant to the potential
for the differential settlement