2. Piers
• Piers are platform built perpendicular or oblique to the shore of a river
or a sea
• In sea, it is constructed where the sea is not deep and harbour is not
convenient for allowing the ships to berth adjacent to the shore
• On both sides of a pier berths are provided
• The length should be sufficient to accommodate the longest ship likely
to take its platform
• The width should be sufficient to satisfy its utility
• May be either open or solid construction
3. 1) Open pier:
• They are built over open water on exposed timber or concrete piles-
RCC or timber is used for decking purpose
• Open piers are used where minimum restriction of currents is
specified
• These piers are relatively more economical as narrow piers in deep
waters
4. 2) Solid pier:
• Solid piers are constructed of materials like earth or rock fill-these
materials are partly confined by some sort of bulk head
• These piers offer more resistance to impact and wave action
• In general solid piers are more stable and economical than open pier
5. Additional points for pier:
• The water area between two adjacent piers is known as slip
• The width of the slip between piers should be at least three or four
times the beam of the largest ships to be accommodated
6. Cont…
• The live loads for pier design depends upon the nature of anticipated
cargo and shipping
• It is usual to provide no space for the purpose of storing cargo on the
pier
• Horizontal thrust on a pier head is taken as about 1% of the maximum
weight of the vessel to be berthed
• Water depth at pier should have a clearance of minimum 30 cm under
the keel of a fully loaded ship with reasonable provision for an
abnormally low tide
8. Wharves
• These are platforms at which vessels take on and discharge
passengers and cargo
• In other words, they are docks that parallels the shore
• Located in such a way as to give sufficient depth of water for the ship
to float
• Generally built continuous with the shore but may not necessarily be
so
• Wharves built parallel with the shore are called quays and walls built
to protect the quays are known as quay walls
• Quay walls are built to retain and protect the embankment or filling
9. Cont…
• The type of vessel to be accommodated governs the length of wharf
and water depth required for berthing of ships
• The wharves design involves the following factors:
1) Provision for berthing of the ship,
2) Handling and storage of cargo
3) Terminal facilities for rail and truck transportation
• Wharves can broadly be classified as open or solid construction
10. Open type wharves
• Open construction wharves can be either high level decks or relieving
type platform
• High level decks have generally a solid deck slab
• Relieving type platform – main structural slab is below the finish deck
and the space between is filled to provide additional weight for
stability
11. Cont…
• Open type construction deck – made of timber or RCC or a
combination of concrete and steel or timber
• Precast or pre-stressed concrete slabs and beam type of decks are
economical
• Deck supported on timber pile but for deep water and soft grounds
pre-stressed concrete piles are best suited
12. Solid type wharves
• Composed of earth or rock fill partly confirmed by some sort of bulkhead
• Various types can be constructed
A. Rock filled steel sheet pile cell bulkhead wharf:
• Suitable - Where water depth < 15 m and bottom conditions are
suitable for support of gravity type of structures
• These cells are capped with a concrete slab and bulkhead wall above
water level
• Steel pile acts in tension to retain the fill inside
• Shell – circular or having circular ends and straight walls
13. B. Bulkhead supported by tie rods and anchor wall:
• Sheet piles may be supported by tie rods attached to an anchor wall or
anchor piles
• The rods should be located at a safe distance in back of the face of the
bulkhead
• Sheet piles should be driven deep enough to act as a cantilever
without additional support in shallow installations
14. C. Bulkhead wharf on closed bottom rock filled concrete caissons:
• Now become quite popular
• Caissons may have open wells and cutting edges to sink below the
dredged bottom to obtain affirm support
• In case of close bottom caissons the foundation should be prepared
consisting of a gravel or crushed stone bed or levelling course
• Heavy pre-cast concrete blocks ( 50 to 200 tonnes) – as gravity quay wall
• Rock fill is placed in back of the wall – to reduce lateral earth pressure
15. Dolphins
• Construction in the form of a cluster of closely spaced piles
• Piles are pulled together at the top and tied by a cable
• Marine structure for mooring vessel
• Generally used in combination with piers and wharves to
shorten the length of these structures
16. Cont…
• Used for tying up ships and also for transferring cargo from one
ship to another when moored along both of their sides
• Dolphins are mainly designed for resisting horizontal impact
force, wind force and water current forces from a vessel when
docking
17. Types of dolphins – as per position
1. Bresting dolphin:
• Having bollards or mooring posts to take the lines of ship and they
move a ship along the dock or hold it against the current
• Provided with fenders to absorb the impact of ship and to protect the
dolphin as well as ship from the damage
2. Mooring dolphin:
• These are additional dolphins and they are provided to hold a ship
against a broadside wind blowing in a direction away from the dock
• They are not designed for the impact of the ship
• So located that the mooring lines are nearly at right angles to the dock
18. Types of dolphin – as per nature
1) Flexible dolphin:
• In the form of cluster of piles tied with galvanized cable
• The piles are in odd numbers of 3, 5, 7, 9 etc.
• Centre pile of each cluster projects about one meter above the other
piles so as to provide means of attaching the mooring lines of a ship
• Piles are arranged with a slight batter and they are distributed
symmetrically
• Piles are used for mooring small vessels up to 50000 kg dead weight
19. Cont…
2) Rigid dolphins:
• Piles of the cluster are bolted to wooden cross members
located just above low water with wooden framing at the top
• Wooden platform type of rigid dolphins are used for larger
cargo ships and tankers
20. Fenders
• A fender in the form of a cushion is provided on a jetty face for
ships to come in contact
• Can be made of different materials in various forms
Classification of fenders:
1) Timber piles fenders with spring
2) Rubber fender
21. Timber piles fenders with spring
• Driven at 3m to 5 m intervals on basin side of quay wall about
0.5 m away from wall
• At top these piles are connected to vertical face of dock or
quay wall through springs
22. Rubber fenders
• Any shaped rubber pads in layers are fixed on vertical face of dock or
quay wall
• These pads may get crushed because of heavy impact of ships
• In case of rubber tubes, steel chain is passing through central hole are
anchored and suspended on thick bolts and nuts on vertical face of quay
wall
