Hydroelastic Response of a Floating Mat-Type Structure in Oblique, Shallow-Water Waves

The linear, Level I Green-Naghdi (GN) theory is developed to study the hydroelastic behavior of a rectangular airport or runway whose draft is "small" and which floats in a near-shore area. The new theoretical and numerical model uses the linear, shallow-water wave equations of the GN type for the fluid dynamics and the thin-plate theory for the structural dynamics. The governing equations are matched at the juncture boundary and the resulting partial differential equations are solved by the boundary-integral-equation method, and the finite-difference method is used for discretizing the boundary conditions at the edges of the plate. The method devised here is proven to be very efficient in a parametric study of the hydroelastic response of a mat-type floating runway in regular, oblique waves. The main parameters varied in the problem are the stiffness, length and beam of the. mat. The deflections of the mat are calculated for various incoming wave frequencies and heading angles in water of "shallow" depth. The results are compared with the available experimental data and numerical calculations by others. The mean drift loads on the mat are also calculated by following Maruo's far-field method.