Zhang, J.; Sun, K.; Zhai, Y.; Zhang, H., and Zhang, C., 2016. Physical study on interactions between waves and a well-mixed seabed. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 198–202. Coconut Creek (Florida), ISSN 0749-0208.
The problem of wave-seabed interaction has attracted more and more attention of coastal researchers and engineers, as it plays an important role in the estimations of seabed stability and foundation design of offshore structures. Much effort has been made by many investigators to study the wave-seabed interaction in the past decades. However, most of them focus on the wave-induced response within a seabed with single/uniform soil particle, ignoring the mixed seabed consisting of different soil particles in the real environment. A series of laboratory experiments are carried out in a wave flume to study the wave-driven pore-water pressure in a well-mixed seabed (consisting of sand and silt) and the attenuation of wave height. Waves propagating over a mixed seabed lead to oscillatory excess pore-water pressures within the porous seabed. Maximum amplitude of the ratio of pore-water pressure within the seabed to pressure on seabed surface decreases within a deeper layer. A phase lag of pore-water pressure is clearly observed, and it contributes to net upward pressure related to seabed instability. The impacts of mixture percentage of sand/silt on pore-water pressure are also analyzed and discussed.