Abstract :
Vertical cuts are prone to several types of failure such as piping, ground
heaving, and deep-seated or base failure. The latter is the subject of this study and
probably attracts less attention in comparison to other types of failure. Although it is
commonly believed that such a failure is rare in normal conditions; in presence of the
seepage flow, deep-seated failure is much likely to initiate and advance prior to other types
of failure. In this paper, the stability analysis of vertical cuts in granular soils in presence
of the seepage flow is studied against the deep failure. To do so, the stability analysis is
made by the use of the well-known method of stress characteristics with inclusion of the
seepage flow force. This nonuniform flow field renders the stability analysis quite complex.
A semi-analytical approach, based on complex algebra, is presented to find the flow field,
which is accurate and much faster for calculation of the seepage force at arbitrary points in
the field. The solution of the flow field is a background solution for the stress field which
is to be found to assess the stability.
