Slope stability

To appreciate that the stability of a natural or artificial slope depends on the geological model, the form of construction and the groundwater or pore pressure conditions. A range of mass movements is possible. To understand that the stability of an artificial cutting, embankment or earth dam is governed by the critical pore pressure conditions. To determine the degree of stability of a slope, considering mass movement with potential failure along a slip surface as a plane translational slide, a circular arc, a non-circular surface or as a number of wedges. Sloping ground can become unstable if the gravity forces acting on a mass of soil exceed the shear strength available at the base of the mass and within it. Movement of the mass of soil down the slope will then occur. This can have catastrophic consequences to life and property if buildings exist on, above or below the slope. An example is the Nicolet landslide, Quebec, Canada (see Figure 12.1).