Mooring Countermeasures for Reduction of Ship Notions due to the Long Period Taves

In Noshiro Port, troubles for cargo handling activity occure by long period waves.In this study, the characteristics of long period ship motions due to long period Waves are examained, and countermeasures of the mooring system which consists of mooring ropes and rubber fenders are also discussed with numerical simulations. For large ship motions, it is confirmed to occur when the dominant period of long period waves agrees with the natural period of surge motion. To reduce ship motions due to long period waves, it is valid to adjust the natural period of mooring systems to avoid dominant period of long period waves.