b. Mode of Failure. The mode of fai

b. Mode of Failure. The mode of failure depends on the relative com-
pressibility of the soil, loading conditions, and geometric considerations
(Vesic 1975). This manual is restricted to general shear failure of shallow
strip foundations, i.e., those whose widths are greater than their embedment.
A general shear failure normally exists for dense sand and stiff clay. How-
ever, for loose sand and soft clay, which may occur more frequently for flood
walls constructed in a flood plain, the bearing capacity should be computed
based upon local shear conditions (Vesic 1975).