This paper is concerned with the dynamic behavior of a flexible circular floating Island subjected to a seaquake, taking Into account the dynamic Interaction effects among a floating Island. anchor system and sea water The floating Island is modeled as an elastic circular plate and the anchor system IS considered to be composed of tension-legs Based on a linear potential flow theory. the hydrodynamic pressure generated on the bottom surface of the Island IS obtained In closed form The modal equations of motion of the Island with or without anchor system is derived by energy method In the formulation the dynamic Interaction effects are estimated as hydrodynamic added mass hydrodynamic added damping and hydrodynamic added stiffness The response quantities are evaluated as root-mean squared values using a linear random vibration theory Numerical examples are presented to discuss the effects of Island flexibility, anchor arrangement anchor stiffness water depth and vertical ground motion characteristics on the seaquake-Induced responses of flexible floating Islands
A seaquake IS the phenomenon of shock waves traveling through the water due to an earthquake with epicenter either on-shore or offshore The shock waves generated In the sea by earthquake motion consist solely of compression wave since water cannot transmit shear wave For a large tanker vessel. It IS expected that Similar damage may be caused by a seaquake With the recent trend toward the construction of large-scaled offshore structures. a number of projects related to the artificial Islands which serve as floating cities or floating airports have been proposed The designs of these large-scaled floating structures demand a better understanding of the dynamic behaviors of structures. In an ocean environment since the deformation of large-scaled floating structures would play an Important role In the overall responses under these circumstances.
