Introduction - Semi-quantitative Approaches for Landslide Assessment and Prediction - page 33

morphology of the moving mass with consideration of mechanism, material and
rate of movement.

1. Con ned failures:

(a) in natural slopes and

(b) in excavated slopes.

2. Rotational slips:

(a) Single rotational slips
(b) Successive rotational slips
(c) Multiple rotational slips.

3. Compound Slides:

(a) In slide mass of low to moderate brittleness

(b) In slide mass of high brittleness.

4. Translational Slides:

(a) Sheet slides
(b) Slab slides; flake slides
(c) Peat slides
(d) Rock slides:

i. planar slides; block slides
ii. Stepped slides
iii. Wedge failures

(e) Slides of debris:

i. Debris-slides: debris avalanches (non-periglacial)
ii. Active layer slides (periglacial)

(f) Sudden spreading failures.

On the basis of Soil Fabric and Pore Water Pressure, Hutchinson (1988) also
classi ed landslides.

A. Soil Fabric [effects on c, ˆ ]

1. First-time Slides in Previously Unsheared Ground: soil fabric tends to be
random and shear strength parameters are at peak or between peak and
residual values.
2. Slides of pre-existing shears associated with:

i. Re-activation of earlier landslides
ii. Initiation of landsliding on pre-existing shear produced by processes
other than earlier landsliding, i.e.:
(a) Tectonics
(b) Glacitectonic