The characteristics of motions of two floating piers moored each other are investigated by using the three dimensional boundary integral equation method. The agreements between the physical and mathematical results of the two floating bodies" motions are fairly well. The influence of mooring forces on motions is calculated. Moreover, the characteristics of motions of a floating body in transient waves like ship waves are investigated using physical model and nonlinear mathematical model.
So many marinas are constructed and planned to prevent illegal mooring of small pleasure boats in Japan. As a floating pier has a sake to reduce the effect of a large tidal range, recently, many types of floating pier have been developed for marina. A floating pier of several pontoons moored to sea bed with poor or hard soil condition by anchor chains in a harbour of deep water, have some advantages from standpoints of good operation and construction cost compared with a pile mooring system. Moreover the chain type is better than the pile type in landscape. It is important for a planning of the floating pier of chain mooring type to know characteristics of motions in wind waves, because the motions of floating pier and mooring forces are influenced by the mooring condition. Since the motions become large unexpectedly when ship waves come to a floating pier, it is also important to know the motions in ship waves.
Works on the hydrodynamic interaction problem have been reported by Ohkusu (1976) and Oortmerssen (1979). The characteristics of linear motions of two floating piers moored each other in monochromatic waves are investigated by using the three dimensional boundary integral equation method with Green's function (Saito and Kubo,1993). The following is a brief explanation of the case of two floating bodies.
