harbour and dock ,wet docks

1. HARBOUR AND DOCK
ENGINEERING
Presentation 5

3. Docks
Docks are
– enclosed areas for berthing ships.
– To Facilitate loading & unloading of cargo and passengers or
for repairs of ships.
Necessity
Docks are necessary for discharging of the cargo as
ships require a number of days for discharging cargo, during
which period they need a uniform water level. If ship is subjected
to a vertical movement by the tides, great inconvenience will be
felt in lifting the cargo from the ship and special arrangement will
be needed for lifting the cargo. 3

4. DOCKS
WET DOCKS DRY DOCKS
To facilitate loading &
unloading of passengers &
Cargo
Used for the repairs of
vessels

5. WET Docks
Wet docks are
 enclosed areas for
berthing ships.
 To Keep them afloat at
a uniform level
 To Facilitate loading &
unloading of cargo and
passengers.

6. ClassifiCation of WEt DoCKs
 Wet docks in tidal basins
 Wet docks in enclosed/impounded basins

7. ClassifiCation of WEt DoCKs ContD…
1.Wet docks in tidal basins
 In low tide areas
 In ports On the open sea coast
protected by an outlying break
water , basins are formed within
its shelter.
 Pier walls are projected at right
angles to shore
 Vessels can lie & discharge cargo
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8. 2.Wet docks in enclosed/
impounded basins
 Docks are formed by enclosures
 Used were tidal ranges are large
 It is shut off at entrances by lock
 Maintain uniform level of water
ClassifiCation of WEt DoCKs ContD…

9. TIDAL BASINS
Basins which are partially
enclosed by water , which
are approached by open
entrances & are subjected
to fluctuations due to
tidal variations.

10. tiDal WEt DoCKs
ADVANTAGES
Vessels can come in,
berth or leave at all times
Speedy &smooth arrival&
departure of ships
Lock gates are not
required
DISADVANTAGES
If range of tide is more
,inconveniences in loading
& unloading
Rubbing of sides of ship

11. ADVANTAGES
Uniform level of water is
maintained
Convenient for handling cargo
Increases the commercial
activities of port
Prevent the rubbing of the
sides of ship
Obviates the necessity of
constant attention to alternation
of mooring
 Effect of storm in the
outer sea & harbour do not
obstruct the dock enclosure
DISADVANTAGE
 Costly arrangements for
locks& gates
 More time for entry & exit of
ship
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ENCLOSED WET DOCKS

12. ShapE Of DOCKS aND BaSiNS:
 Shape of dock or basin should be straight to facilitate the ships
to stand along them, as curved shape is not convenient for
ships to stand along side.
 The shape of docks and basins should be such that maximum
quayage i.e. berthing length is available within the given area.
The shape has therefore essentially to be made up of a number
of straight patterns as curved lines are unsuitable for berthing
of the ship.
The following are the shapes may be adopted as per site
conditions:
 Rectangular dock
 Diamond dock
 Inclined Quay type.

13. 1. Rectangular dock: The length and breadth should be adjusted in
such a way as to give maximum quayage

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RECTANGULAR BASIN DOCKS

15. 2.Diamond Dock:
For the same perpendicular distance between long
sides, the long side could be extended conveniently.
3.Inclined Quay dock:
It consists of a number of projecting quays into the
dock or basin.

16. Location of dock
Docks can be located on inland ports of rivers or at estuaries
or open sea coasts. A proper piloting service is necessary. The river
approaches to the dock have to be maintained.
internaL arrangements
Generally different docks are required for different types of
cargo. For example coal and oil should be deal with separate way
from food or general cargo.

17. other aspects or requirements:
 Approaches must be of sufficient depth and sheltered. In many
cases approach channels both on the open coast and island
docks have to be dredged frequently.
 Availability of fresh water to replace fouled and leaked water
from docks.
 In inland to replace the fouled water from docks, separate
canals from the rivers have to be provided, if alternate sources
of water supply are not available. In case of sea coast docks,
the sea water could be used for cleaning and replenishing the
dock.

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