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TTE TTE-6755 Port Planning and Design 6755 Port Planning and Design Lecture #17 Lecture #17 Moorings and Fenders Luis Prieto-Portar 2009 Introduction. When the earliest seafarers set sail in search of new lands, food or trade they secured their vessels either by beaching them or tethering those craft to shore with a mooring line. As craft become bigger and larger and regular patterns of trading were established, ports were built allowing vessels to berth to a wharf. A mooring is defined as a compliant (usually a tensile structure) that restrains a vessel against the forces of the sea and the movements generated by wind, wave, and currents acting upon the vessel. For thousands of years, the traditional practice of mooring with ropes has remained unchanged. Even today, the traditional mooring is essentially as it was at the beginning of last millennium. Mooring Points. A mooring is a structure that restrains a vessel against forces generated by wind, waves, and current forces. The purpose of moorings are, 1) Loading/unloading stores, cargo, fuel, personnel, ammunition, etc; 2) Ship storage to reduces fuel consumption and personnel costs; 3) Maintenance and repairs are easier to perform; 4) Mission support such as surveillance, tracking, training, etc; 5) Reduce the ships motions and the dynamic loads that are produced by waves. For harbors, marine terminals, floating terminals and offshore structures, optimizing e mooring system is important for improving safety and minimizing downtime. the mooring system is important for improving safety and minimizing downtime. Moored objects are subject to external forces in the form of wind, waves, current and interaction effects from passing ships. These forces may have various impacts, including: 1- Hampering the cargo handling operations due to large motions (downtime); 2- Damaging the moorings due to large loads; 3- Endangering ship' s crew and terminal personnel; 4- Causing discomfort for passengers of cruise-vessels and pleasure craft. Mooring Systems. A) Fixed mooring systems , consists of a structural element permanently fixed in position to which a vessel is moored. These structural elements include: (i) Platforms, (ii) Cells, (iii) Dolphins, (iv) Spuds, and (v) Bollards. ) leet mooring systems re structural elements that are not permanently fixed in B) Fleet mooring systems are structural elements that are not permanently fixed in position, such as buoys, ships anchor systems, lines, anchors, etc. C) A pile system . D) The mooring line system : (i) Natural fiber rope, (ii) Synthetic-fiber rope, (iii) Wire rope, and (iv) Mooring chains. The (i) mooring platforms consist of isolated concrete, steel, or timber decks supported on concrete, steel or timber piling. A platform may be used as a mooring structure (a mooring platform) or a breasting structure (a breasting platform). ... View Full Document

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