Studies on the effect of non-linear wave loading in shallow water region on dynamic response of sandy seabed

In this study, numerical analyses for solving the generalized Biot's dynamic consolidation equations by virtue of finite element method are performed on dynamic response of sandy seabed subjected to non-linear wave loading in the shallow water region. The seabed is modeled as poro-elastic media and the non-linear wave loading is represented by second-order Stokes'wave theory and first-order cnoidal-wave theory. Numerical results are given for comparative studies. Compared with the numerical results from the linear wave theory, the amplitudes of both pore water pressure and effective pressure computed from the non-linear wave theories increase. It is shown that the linear theory of wave usually under-evaluates the dynamic response of seabed in the shallow water region. Therefore, the effect of non-linear characteristics of wave loading should be taken into consideration in planning and design of various near-shore or offshore constructions and facilities and in evaluation of engineering sites.