Simplified Methods for Plane Failure

The purpose of this chapter is to present some simple equations for determining the safety factor of slopes with plane failure surfaces. Only three simple cases will be considered: one involving an infinite slope with a failure plane parallel to the slope surface, one involving a triangular cross section with a single failure plane, and the other involving a trapezoidal cross section with two failure planes (Huang, 1977a, 1978b). For three failure planes, the computerized method presented in Chap. 8 should be used.