FULL-SCALE DECAY TEST OF A TANKER - FIELD DATA AND THEORETICAL-ANALYSIS

This paper presents results from a full scale decay test made with a t anker in a relatively protected area in the Brazilian coast. In at lea st two tests the environmental loads (wind, waves and current) were ve ry small and the time history of the surge motion was well behaved, ma king it possible to check some proposed models for the damping in the hull and mooring lines. Field data seem to confirm that the damping is indeed of the fluid viscosity type and the theoretical models are abl e to recover roughly 75% of the observed damping, the energy dissipati on in the mooring lines being, by far, the major contribution. The rem aining 25% are likely due to non modeled effects, such as the environm ent influence, which although small and not measured certainly exists, and to the friction between the mooring lines and the seabed. (C) 199 8 Published by Elsevier Science Ltd. All rights reserved.