Numerical analysis of wave induced porous fluid pressure on three-dimensional structure of arbitrary shape resting on seabed : Dahong Qiu; Jun Zang Proc 10th International Conference on Offshore Mechanics and Arctic Engineering, Stavanger, 23–28 June 1991V1-Part B, P475–480. Publ New York: ASME, 1991

Abstract

In this paper, a numerical method to determine the wave induced uplifting force and overturning moment acting on the bottom of an arbitrary shaped structure resting on seabed is presented. Two kinds of seabed are considered. One is homogeneous, isotropic, and has linear elastic behaviour, the other is anisotropic and contains partly of rubble-mound seabed. It is assumed that the seepage action in rubble-mound seabed is expressed by non-Darcy's seepage flow. The seepage resistant force satisfies Forcheimer's formula. The Seepage action in soil seabed is expressed by Darcy's law. The displacements of soil and porous fluid pressure satisfy Biot consolidation theory. The fluid is compressible. Yamamoto's results were accepted in the far field boundary conditions. Because the displacements of soil and the porous fluid pressure are coupled in Biot consolidation theory, it is difficult to solve. Kokkinowrachos combines the storage equation with Biot equations, eliminates the soil displacements from the above equations. By using this equation, numerical solutions for the seepage pressure are presented for the structures mentioned above in this paper. The main contribution of this paper is that rubble-mound seabed and three-dimensional structure of arbitrary shape are considered, the wave induced porous fluid pressure is obtained by the finite element method. The calculated results for some examples are presented and evaluated.