Page 110 - Navy Journal 219

Navy Journal 2019

Steps created by this method may also reduce surface erosion. However, caution is
necessary to avoid the onset of local breakage following the cuts.
Fig 3: Geometric modification or slope trimming technique against landslide

Cut too high
Slope Stake
Cut too low
Overstoopered cut slope
Designer Cross Section
Excess
Excavation

Surface erosion control. Water near the surface of the hillside can cause the
erosion of surface material due to water runoff. This process tends to weaken the
slope by removing material and triggering excess pore pressures due to the water
flow. For defence against erosion, several solutions may be used. There are few
measures to share the superficial character of their installation and low
environmental impact.
a. Geo-mats are anti-eroding bio-mats or bio-nets that are purpose-made
synthetic products for the protection and grassing of slopes subject to
surface wash. Geo-mats provide two main erosion control mechanisms for
containment and reinforcement of the superficial ground and protection
from the impact of the raindrops. Another material geo-grids made of
geo-synthetic materials.
b. Steel wire mesh may be used for soil and rock slope stabilization. After
leveling, the surface is covered by a steel-wire mesh, which is fastened to
the slope and tensioned. It is a cost-effective approach-wicker or
brushwood mats made of vegetable material. Very long and flexible willow
branches can be used, which are then covered with infill soil.
c. Alternating stakes of different woody species are used and they are
woven to form a barrier against the downward drag of the material eroded
by free water on the surface.

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