APPROXIMATE CALCULATION OF SHIP MOTIONS UNDER THE PREVENTION SYSTEM OF SHIP SEPARATION FROM QUAY WALL

In a previous paper, model tests under wave action were carried out in order to investigate motions of a ship moored by the prevention system of ship separation from a quay wall. In this paper, an approximation method is introduced to calculate ship motions under this system. The results obtained are as follows; (1) Excluding the wave forces and moments over a range of the prevention system, moored ship motions under the system can be calculated. (2) The ratio of dynamic wave force to static force of the system can be calculated, and the experiments performed under the same order of both forces. (3) Even if the horizontal wave moment is larger than the static moment of the system, roll motions become smaller by an increased damping force due to the ship side wall contact with the fender.