Embankment for rock
fall protection
Passive protection structures are typically placed
so as to intercept the block's trajectory during movement and fall;
therefore the definition of the block motion is of utmost importance
for a correct design. The choice and design of the correct structure
of passive protection can be made when the best position, height
and kinetic energy to absorb are defined. Among passive protection
structures, embankments for rock fall protection have great importance,
as they offer the best performances in terms of protection efficiency
in comparison to a high-energy absorption wire netting rock protection
barrier. |
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Reinforced soil rock fall protection embankments assure:
- efficiency of protection even in case of repeated collapses
along the same section;
- reduced maintenance even after large detachment of blocks;
- long term structure's durability without collapse or decay
even further to phenomena such as fires;
- reduced environmental impact, particularly if the structure
is masked with adequate naturalistic engineering work;
- possibility to re-use previously collapsed or discharge material
coming from landslide's alluvial cone.
The evident advantages present in a reinforced
soil embankment compared to a traditional structure are certainly:
a space saving at the base, an increase in the resistance at the
impact with minimum damages, a better energy absorption with minimum
possibility of breaking caused by a boulder with high energy. These
two last characteristics can be proved only when referred to a reinforced
soil embankment; indeed, in such structures the ground is tied by
the geogrids both in the longitudinal and transversal direction
of the structure; therefore to break the reinforced embankment,
the boulder first shall tear the grids, which however offer high
resistance to tensile strength and pullout.
HDPE extruded geogrids TENAX TT SAMP are ideal for such applications
as they have an elastic-plastic behavior so that they quickly react
to the applied loads with an increase of the elastic modulus, as
in the case of an impact therefore the whole tensile resistance
of the geogrid can be mobilized.
Geogrids allow an increase of the dynamic dumping characteristics
of the reinforced soil compared to soil on its own, both through
the energy that is directly absorbed by the geogrid itself and though
the "Coulomb dumping effect" due to friction generated
in the dynamic stage. A major "confinement" of the ground
means a distribution of the dynamic loads on a cone with a larger
opening, and therefore a greater mass of soil involved in the resistance
to hit and to energy dissipation.
Reinforced ground barriers with TENAX TT SAMP geogrids have been
tested in a full scale testing facility accredited by Politecnico
di Torino, which, further to such tests, issued a certificate to
TENAX Company, attesting the capacity of the barriers to withstand
impacts up to 3000 kJ.
Another certificate confirming the test result carried out with
an impact of more than 4000 kJ of energy, already performed, will
be soon released. |