Experimental study of pore water pressure response in sandy seabed under breaking wave action
Based on the wave flume experiments,the response pattern of excess pore water pressure is studied on a 1∶30 slope sandy seabed under the regular breaking wave action.The topographic change is observed and its causes are analyzed in the broken wave zone.The results show that the excess pore pressure changes significantly and differently before and after wave breaking.The excess pore water pressure reaches the maximum on the area away from the nearest bed surface of the breaking point in the whole process,and the vertical decay rate of excess pore water pressure is larger than the before and after wave breaking in the broken zone.The excess pore water pressure increases significantly at the breaking point.Before and after the wave breaking,the change between excess pore water pressure and wave height has positive correlation trend,and the correlation is not very well after the wave breaking.The topographic change is great in the wave breaking zone.Excess pore water pressures changing at the top are significantly higher than it is at the bottom.When the sand scours,the amplitude of the excess pore water pressure increases.And when the sand accumulates,the amplitude of the excess pore water pressure decreases.