Groundwater Seepage Vectors and the Potential for Hillslope Failure and Debris Flow Mobilization

Water Resources Research
By:  and 



Insight for understanding the effect of groundwater flow on the potential for hillslope failure and liquefaction is provided by a novel limit‐equilibrium analysis of infinite slopes with steady, uniform Darcian seepage of arbitrary magnitude and direction. Normalization of the limit‐equilibrium solution shows that three dimensionless parameters govern completely the Coulomb failure potential of saturated, cohesionless, infinite homogeneous hillslopes: (1) the ratio of seepage force magnitude to gravitational body force magnitude; (2) the angle θ − Φ, where θ is the surface slope angle and Φ is the angle of internal friction of the soil; and (3) the angle λ + Φ, where λ is the angle of the seepage vector measured with respect to an outward‐directed surface‐normal vector. An additional dimensionless parameter affects the solution if soil cohesion is included in the analysis. Representation of the normalized solution as a single family of curves shows that minimum slope stability universally occurs when the seepage direction is given by λ = 90° − Φ. It also shows that for some upward seepage conditions, slope stability is limited by static liquefaction rather than by Coulomb failure. Close association between these liquefaction conditions and certain Coulomb failure conditions indicates that slope failure in such instances could be responsible for nearly spontaneous mobilization of destructive flowing soil masses on hillslopes.

Publication type Article
Publication Subtype Journal Article
Title Groundwater Seepage Vectors and the Potential for Hillslope Failure and Debris Flow Mobilization
Series title Water Resources Research
DOI 10.1029/WR022i011p01543
Volume 22
Issue 11
Year Published 1986
Language English
Publisher American Geophysical Union
Description 6 p.
First page 1543
Last page 1548
Google Analytic Metrics Metrics page
Additional publication details