4. Coastal Erosion and Protection Measures Including Case Studies
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Elev. 2.5 m
Armour Stone
Elev. 0.0 m MSL
Ground Level
Concrète Cap
Elev. - 0.2 m
Gravel Blanket 0.25m thick
Well graded bank
Fig. 4.9 Cross-section of quarry stone revetment.
Training walls
They are usually constructed at tidal inlets and as the name suggests their
primary purpose is to train the river mouths. These structures propagate
from the river mouth into the sea, facilitating tidal flushing; preventing
sand bar formation and clogging of river mouths. Typical layouts showing
the effect of training walls at the mouth of Perumanathura (8°37'59.41"N
and 76°47'11.98'/E) along the Southwest coast of India are shown
in Fig. 4.10.
Fig. 4.10 Google earth imagery of Perumanathura.
4.5.2.2 Soft structures
Soft engineering options dissipate incident wave energy, the extent of
which dépends on the nature of the protection measure, wave and