| The interaction of water waves with cohesive sediments is explored in this study from two aspects. The rheological properties of soft muds, kaonilite and montmorillonite, were measured under oscillatory motions that were similar to wave forcing. Those rheological parameters were then coupled with predictive models to simulate the wave-muddy bottom interaction.;The tested muds have rheological responses that depend on the amplitude of the imposed strain. Muds behave as elastic solids at small strains, as viscous fluids at large strains, and as viscoelastic material in between. Empirical relationships between rheological parameters, such as the storage modulus, G;Two predictive mathematical models were developed in this study to simulate the wave-muddy bottom interaction, and both models were successfully compared with previous models. The first one is a complete layered viscoelastic model (CVM). This model regards muds as general viscoelastic material, from viscous fluids to elastic solids, and the stratification of muds can be simulated by three constitutively different layers. For a finite unconsolidated mud, the CVM predicted that wave-induced mud fluidization is initiated at the mud bottom and the fluidized zone expands upward with increasing wave height. In such case, the wave damping rate decreases with the increasing wave height. For a deep consolidated mud, the wave-induced mud fluidization starts from the mudline and expands downward. The corresponding damping rate in this case increases with the increasing wave height, since the loss modulus or viscosity of the fluid mud increases downward. In order to highlight the peak wave damping phenomenon, a viscoelastic boundary layer model was developed and the mud thickness for peak damping was expressed for some special cases. |
