Single-component sliding block analyses produce results that
are consistent with multiple-component analyses for relatively
flat ~less than about 10°–15°! slopes. Singlecomponent
analyses generally tend to underpredict displacements
for slopes whose stability is governed by frictional
strength, and overpredict displacements for slopes with cohesive
strength. For steeper slopes, the predictions of singlecomponent
models diverge from those of multicomponent
models by an amount that increases with increasing slope
inclination and increasing static factor of safety. The component
of motion parallel to the strike of the slope has little
influence on the permanent displacement of most slopes, unless
the failure surface is significantly asymmetric or the
slope is kinematically unconstrained against displacement in
that direction.