marine coastal structure

1. WEST BENGAL UNIVERSITY OF ANIMAL AND FISHERY SCIENCES
A SEMINAR ON : MARINE COASTAL STRUCTURES
SUBMITTED TO:
Dr. S.K.Rout
Dept. of AEM
SUBMITTED BY:
Shirsak Mondal
B.F.Sc 1st Year 2nd Sem
FS/2015/31

2. What ARE Marine Coastal
StructureS?
It can be anything human-made in
the coastal area. They are
constructed principally to protect the
coast line.

3. WHAT DO COASTAL STRUCTURES DO ?
1. Stop Water 2.Hold Soil
Protect Infrastructure from flooding due to high
water levels ,erosion and impact from waves and
currents
Protect boat traffic by reducing waves and wave
impact
Stabilize navigation channels by reducing
sedimentation, inlet migration
Reduce erosion by stabilizing shorelines/beaches
Enhance recreation, beauty

4. DIFFERENT TYPES OF COASTAL
STRUCTURES
On the basis of purposes there are different
types of coastal structures.
They are :-
Revetments
Bulkheads and Seawalls
Breakwaters
Groins and jetties
Coastal bridges and piers
Dikes and levees

5. Revetments
Revetments are shoreline structures constructed parallel to
the shoreline
 Revetments are structures placed on bank or cliffs in such a
way as to absorb the energy of incoming water or explosive
caused by water waves and current
A cheaper alternative to sea walls is the revetment ,usually
built for protection

6. •Modern revetments have concrete or shaped blocks of rip
rap stone laid on top of a layer of finer material
•Rip rap has the advantage of good permeability plus it
looks more natural

7. Bulkheads
Bulkheads are vertical retaining walls to hold
or prevent the soil from sliding seaward
It reduces land erosion
Secondary purpose is to protect upland
areas against damage from wave action.

8. Seawalls
It is formed for hard and strong coastal
defence constructed on the inland part of
a coast to reduce the effects of strong
waves
It separate the land & water

9. Curved Sea-wall
Curved or stepped sea walls are
designed to enable wave to break
and to dissipate wave energy and
repel waves back to the sea

10. Seawalls are
vertical
structures
constructed
parallel along
the shore line
It should last
20-30 years

11. Breakwaters
Breakwaters are large scale structures constructed
seaward of, & usually to the shoreline

12. They attempt to break incoming waves
before they reach the shoreline or the facility
(e.g. Marina) they are protecting

13. Single Breakwaters:
Single breakwaters may
be attached or detached ,
depending on what they
are being designed to
protect

14. Groins
Groins are the oldest and most common shore-connected,
beach stabilization structure
They help to create or widen beaches by capturing sand
moving along the shoreline

16. Characteristics of Groins
 they are usually made of tropical hardwoods which are
more resistant to marine borers and erosion
 a few are made of concrete, steel or in more recent
times large rocks
 they are spaced about 50-100 metres apart
 may have a life of 15-20 years

17. Jetties & Piers
a structure extended into a sea, lake or
river to influence the current or tide or to
protect a harbour

18. Coastal Bridges
Pictures of coastal bridges

19. Dikes
dikes are typically earth
structures
 they keep elevated water
levels from flooding interior
lowlands
 sometimes they refer to as
dam

20. River dike