Marine Structures Definition of Terms

Definition of Terms

Dock - a general term used to describe a marine structure for the mooring and tieing up of vessels, for loading and unloading cargo, or for embarking and disembarking passengers
- referred to as pier, wharf, bulkhead or in European terminology, a jetty, quay, or quay wall

Wet Dock - in Europe, docks are knows as wet dock due to large variations in tide level; an artifical basin for vessels

Dry Dock - artificial basin where the basin is pumped out'

Wharf or Quay - a dock which parallels the shore; generally contiguous with the shore; used for docking at one side only

Bulkhead or Quay Wall - a dock which parallels the shore and is backed up by ground; it supports/holds the ground in back of it

Bulkhead - installed to retain the made ground which is at higher elevation than the waterway; this is done in cases where plants need to be built adjacent the shoreline where the marshy soil will be filled by dredging the adjacent waterway

Bulkhead wharf - part of a bulkhead used as a wharf for docking vessels by addition of mooring apurtenances, paving, and facilities for handling and storing cargo

Pier or Jetty - dock which projects into the water; sometimes referred to as a mole; can be used for docking on both sides; may be more or less parallel to the shore and connected to it at right angles to the pier through mole or trestle (referred as T-head pier or L-shaped pier depending on the approach if at center or at end)

Breakwater Pier - a pier or jetty combined with breakwater;

Dolphins - maritime structures for mooring vessels; used in combination with piers and wharves to shorten the lengths of the piers and warves; principal part of fixed-mooring-berth type of installation used extensively in bulk cargo loading and unloading; also used for tying up ships and for transferring cargo from one ship to another when moored along both sides of dolphins; TWO TYPES : BREASTING and MOORING

BREASTING DOLPHINS - larger than mooring; designed to take the impact of the ship when docking and to hold the ship agaisnt a broadside wind; provided with fenders to absorb the impact of the ship and to protect the dolphin and the ship from damage; usually have bollards or mooring posts to take the ship lines, particularly springing lines for moving the ship along the dock or holding it against the current

Mooring dolphins - additional dolphins installed provided off the bow and stern , located some distance in back of the face of the dock; privided because the springing lines are not very effective in a direction normal to the dock, particularly when the ship is light; provided to hold the ship against broadside wind blowing in a direction away from the dock; not designed for the impact of the ship as they are located in back of the face of the dock where they will not be hit; effective when installed about 45 degress off the bow and stern and mooring lines will not be less than 200 ft nor more than 400 ft long and when only two will be used; largest ships may require additional 2 dolphins off the bow and stern and these are located so that mooring lines will be normal to the dock which makes the most effective in holding the ship against offshore wind; provided with bollards or mooring posts and with capstans when heavy lines are to be handheld;
maximum pull on single line may not exceed 50 tons or 100 tons on a single bollard if two lines are used

Fixed mooring berth - marine structure consisting of dolphins for tying up the ship and a paltform for supporting the cargo-handling equipment; platform is set back 5 to 10 ft from face of the dolphins so that the ship will not come in contact with it, and therefore does not have to be designed to take the impact of the ship

Moorings for ships - consist of ground tackle placed in fixed positions for attaching the ship's lines; each unit consist of one or more anchors with chani, sinker, and buoy to which the lines are attached; these are located so as to take the bow and stern lines; one or more breasting lines are needed for large ships; for some moorings where the wind is in one direction, the ship may use its own bow anchor and the fixed tackle off the bow may be omitted

References:
DeF Quinn, A. Design and Construction of Ports and Marine Structures. New York, 1972. page 265-267.