Numerical Response Analysis of a Large Mat-type Floating Structure in Regular Waves

Recently large floating structures which may be used as a floating airport have been studied actively. National project of developing very large floating structures has been in progress in Japan as well. This very large structure is relatively flexisible compared with real floating structures like large ships. When we estimate dynamic responses of these structure, fluid-structure interation cannot be ignored because elastic deformation as well as rigid motion of the structure produces hydrodynamic forces. In the present study, we have developed a numerical code for dynamic response analysis of a flexible floating structure of mat-type in regular waves. The floating structure is treated as a rectangular flat plate by use of finite elements, and boundary elements are used in the formulation of the sea region. The present numerical results agree well with numerical or experimental results reported by SRI. In order to know the characteristics of the dynamic response of the larger floating structures, effects of bending rigidity of the structure and wave direction on dynamic response of the strucuture are studied by use of numerical calculation. And it is also shown that the dynamic response for larger L/λ is proved to be very similar to that caused by concentrated exciting force on an edge.