Page 109 - Navy Journal 219

Landslide in Hilly ...

Fig 2: Types of landslide

SLIDE (ROTATIONAL) SLIDE (TRANSLATIONAL) EARTHFLOW

Protection measures from Landslide disaster
The protection of natural and quarry faces can have two different aims.
Firstly, protecting the rock from alteration or weathering and secondly, protecting
infrastructure and towns from rock falls. Identification of the cause of alteration or
the possibility of rock fall allows mitigation measures to be tailored to individual
sites. The most-used passive protection measures are boulder-gathering trenches at
the foot of the hillside, metal containment nets, and boulder barriers. Boulder
barriers are generally composed of suitably rigid metal nets. Various structural
types are on the market, for which the manufactures specify the kinetic energy of
absorption based on an elemental analysis of the structure under projectile
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collision conditions. Few suggestive measures are appended below:
Geometry modification. The operation of re-profiling a slope with the aim of
improving its stability can be achieved by either lowering the angle of the slope
or positioning infill at the foot of the slope. Slope angles can be reduced by
digging out the brow of the slope, usually in a step-wise fashion. This method is
effective for correcting shallow forms of instability, where movement is limited
to layers of ground near the surface and when the slopes are higher than 5m.

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