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Coastal Engineering: Theory and Practice
Tetrapod
These are tetrahedral blocks used as armour for the breakwaters. Its shape
allows it to dissipate the incoming wave, thus allowing the water to flow
around. It reduces the displacement of rubble mound by allowing a random
distribution of tetrapods to interlock. The tetrapods tend to get dislodge
by the crashing wave and hence they are often numbered to monitor any
displacement.
(ii) Complex shape: Because of its complex shape, the interlocking of
armour blocks governs the stability factor. Distinctive type of this génération armour units are stabit and Dolos.
Dolos
These are made from un-reinforced concrète, poured into a Steel mound.
In the absence of reinforcement, Steel fibers are mixed to the concrète for
higher stability. These are limited to be installed near the coast for its heavy
weight. These are used to protect harbour walls, breakwater and shorelines.
They can trap sea-sand thus preventing érosions. They are highly stable
and do not dislodge easily. They dissipate the waves by deflecting the wave
energy. The stability coefficient, Kd which dépends on the number of layers
to be adopted, its slope as well as the nature of waves (breaking or nonbreaking) is derived through physical model tests by subjecting the cross
section to the action of 500 to 100 waves. The Kjj for the different CAUs
are projected in Table 5.1.
5.6 Kolos
5.6.1 General
Kolos, a concrète armour module is designed and developed from Dolos. It is
regarded as a two elongated concrète members connected on opposite sides
by a short central shank. The longitudinal axes of outer elongated members
are parallel and linked with a central shank of which the longitudinal axis
is normal to the outer members. The cross-section of outer members are
octagonal with decrease in area towards the end. An isométrie view of a
Kolos is illustrated in Fig. 5.9. Through a comprehensive physical model
testing program, the authors hâve found the range of stability coefficient
for KOLOS for the trunk and head portion were found to be in the range,
23 to 32 and 3.5 to 8 for the trunk head portions, respectively. The above
said details are discussed under Sec. 5.7.
Coastal Engineering: Theory and Practice
Tetrapod
These are tetrahedral blocks used as armour for the breakwaters. Its shape
allows it to dissipate the incoming wave, thus allowing the water to flow
around. It reduces the displacement of rubble mound by allowing a random
distribution of tetrapods to interlock. The tetrapods tend to get dislodge
by the crashing wave and hence they are often numbered to monitor any
displacement.
(ii) Complex shape: Because of its complex shape, the interlocking of
armour blocks governs the stability factor. Distinctive type of this génération armour units are stabit and Dolos.
Dolos
These are made from un-reinforced concrète, poured into a Steel mound.
In the absence of reinforcement, Steel fibers are mixed to the concrète for
higher stability. These are limited to be installed near the coast for its heavy
weight. These are used to protect harbour walls, breakwater and shorelines.
They can trap sea-sand thus preventing érosions. They are highly stable
and do not dislodge easily. They dissipate the waves by deflecting the wave
energy. The stability coefficient, Kd which dépends on the number of layers
to be adopted, its slope as well as the nature of waves (breaking or nonbreaking) is derived through physical model tests by subjecting the cross
section to the action of 500 to 100 waves. The Kjj for the different CAUs
are projected in Table 5.1.
5.6 Kolos
5.6.1 General
Kolos, a concrète armour module is designed and developed from Dolos. It is
regarded as a two elongated concrète members connected on opposite sides
by a short central shank. The longitudinal axes of outer elongated members
are parallel and linked with a central shank of which the longitudinal axis
is normal to the outer members. The cross-section of outer members are
octagonal with decrease in area towards the end. An isométrie view of a
Kolos is illustrated in Fig. 5.9. Through a comprehensive physical model
testing program, the authors hâve found the range of stability coefficient
for KOLOS for the trunk and head portion were found to be in the range,
23 to 32 and 3.5 to 8 for the trunk head portions, respectively. The above
said details are discussed under Sec. 5.7.