THE DYNAMICS OF VESSELS MOORED BY MULTIPLE CABLES IN DEEPWATER

The station-keeping response of a moored construction vessels, such as pipelay barges, is an important consideration for determining operational constraints. Station-keeping is best characterized by the slow drifing motions of the vessel within the constraints of the mooring system. This paper presents an analysis to evaluate the dynamics of an offshore construction barge moored by a system of single-component cables in deep seas subjected to arbitrary time-varying external forces such as waves, wind and current. The vessel is mathematically modelled as a rigid body with a discrete point of attachment for each mooring line. Each mooring line is treated as a single-component cable terminating at a gravity-type anchor. The limiting tensions for each cable in complete and partial catenary configurations are determined from the cable strength and anchor holding capacity. The effects of system damping and cable stretch are included. Numerical results obtained for a typical cases are presented and compared to model test results.

• Supplemental Notes:
  • Presented to SNAME, New Orleans, Louisiana, January 19, 1978.
• Corporate Authors:

  Society of Naval Architects and Marine Engineers

  601 Pavonia Avenue
  Jersey City, NJ  United States  07306-2907
• Authors:
  • Hairston, D E
• Publication Date: 1978

Media Info

• Features: References;
• Pagination: 26 p.

Subject/Index Terms

• TRT Terms: Anchoring; Cables; Dynamic loads; Dynamics; Force; Mathematical models; Mooring; Mooring cables; Moorings; Ocean currents; Offshore moorings; Ship operations; Waves
• Uncontrolled Terms: Dynamic response
• Old TRIS Terms: Anchor holding power; Cable dynamics; Current forces; Moored vessels; Station keeping; Wave forces on structures; Wind forces on structures
• Subject Areas: Hydraulics and Hydrology; Marine Transportation; Terminals and Facilities;

Filing Info

• Accession Number: 00173985
• Record Type: Publication
• Source Agency: Society of Naval Architects and Marine Engineers
• Files: TRIS
• Created Date: May 3 1978 12:00AM