Coastal mooring design: taut elastomeric and chain catenary surface buoy moorings

A comparison is made of the behavior of a buoy anchored with an elastomeric tether and a chain catenary mooring at the same water depth and under the same environmental conditions. The results include numerical predictions of the statics and dynamics of the two moorings under identical ocean current and sea state forcing. The at-sea recorded tensions in an elastomeric tension member buoy system are also studied. The results show that elastomeric tethers respond with one third of the dynamic tensions of a chain catenary mooring in severe sea states. The chain moorings also experience considerable frictional wear due to chain links interacting with the sea bottom. A drawback of elastomeric tether moorings is that they can be damaged or cut when entangled with fishing gear.