ABSTRACT
Infiltration plays a significant role in the instability of slopes (Zhang et al., 2011). The effect of seepage and infiltration on slope stability is traditionally addressed by calculating the factor of safety or critical depth for an infinite slope subject to seepage parallel to the slope surface. This type of analysis assumes that saturated steady-state flow takes place over a given depth. To simplify the analysis as a worst-infiltration scenario, it is often assumed that the phreatic surface rises to coincide with the slope surface and that the slope is completely saturated (Collins and Znidarcic, 2004). For such fully saturated slopes, additional infiltration is not possible and rainfall will have no further effect on slope stability.
