Wave Interaction with Seabed

The value of L and d is obtained from the Airy wave theory. 

Relationships between wave profile, wavelength, and wave pressure on rigid seafloor. (From Seed, H.B., and M.S. Rahman, Marine Geotech., 3,123-150,1978. Reprinted with permission of Taylor Francis Group.) 

H is the double amplitude of wave Yo, is the unit weight of water 

The general ocean wave problem differs from the earthquake problem in four major 

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There have been a number of analytical studies that have examined the hydraulics of waves interacting with the seabed under a variety of conditions. Some of these conditions are the following ... 

The propagation of water waves over a permeable seabed exerts a time varying pressure at the sediment/water interface. The time varying pressure will cause cyclic variations in pore pressure and stresses within the bed. The effective stress varies in response to wave loading. Since soil strength is directly related to effective stress, any change in the effective stress state within the bed will affect bed strength and stability. Many coastal structures such as pipelines, platforms, anchors, and breakwaters that interact with the seabed will be affected by both cyclic effective stresses and the erosion potential of the bottom sediments. 

Infragravity waves with a period of about 1 min having a duration about 2 hrs and a non-regular occurrence pattern were seen during the SIMI experiment. Such a spectral structure leads us to assume that the origin of the waves is more likely to be related to non-regular events such as oscillations of the seabed due to seismic activity or to nonlinear interactions between swell waves of short periods. 

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