A dolphin is an isolated marine structure for berthing and mooring of
vessels. It is not uncommon that the combination of dolphins with piers could drastically reduce the size of piers.
Dolphins are generally divided into two types, namely breasting dolphins and mooring dolphins. Breasting dolphins serves the following purposes:
(i) Assist in berthing of vessels by taking up some berthing loads.
(ii) Keep the vessel from pressing against the pier structure.
(iii) Serve as mooring points to restrict the longitudinal movement of the berthing vessel.
Mooring dolphins, as the name implies, are used for mooring only and for securing the vessels by using ropes. They are also commonly used near pier structures to control the transverse movement of berthing vessels.
This question is taken from book named – A Closer Look at Prevailing Civil Engineering Practice – What, Why and How by Vincent T. H. CHU.
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