Key geological issues - Geotechnical Engineering of Dams - page 66

Hi gh lateral margin
influence σ n on rupture

surface, usually following
clay/marl/s hal e layer.

Very high

α

av

α ≈ φ r

Large Rock Glide

Rupture surface follows stress relief
cracking or joints
La rge difference between peak and
residual friction angles.

α av

α ≈ φ r

Dominant rock mass
anisotropy dips into
slope

Rough Translational Slide

Planar bedding or
major structures

α av

α av ≈ φ

r

Planar Translational Slide

α av > φ

r '

Localised buckling failure of
str at a at toe

α av

Toe Buckling Translational Slide

Figure 2.44. Summary of features of large rapid rock landslides - Sheet 1 of 2 (Glastonbury 2002,

Glastonbury & Fell 2002c).