Stabilization of a Rock Mass Slide - Rock Mechanics Based on an Anisotropic Jointed Rock Model - page 815

allel discontinuities. The back analysis yielded a friction angle on the bedding-parallel
discontinuities of only φ B = 9.5° (Fig. 25.20). Thus it was concluded that the rock slide

of the southern slope was initiated as a toppling failure (Rensing & Pierau 2006, and
Sections 11.2 and 11.4).
In addition, the relatively deformable anticline is compressed due to stress concentra-
tions resulting from excavation. This leads to vertical displacements towards the cut in
this area (Fig. 25.21).

Figure 25.21 Calculated displacements due to excavation to lower berm (Rensing & Pierau 2006)

Figure 25.22 Horizontal displacements due to excavation to lower berm, comparison
of measured and calculated displacements