WAVE-INDUCED FLUIDIZATION OF COHESIVE SEDIMENT BEDS

In this paper, the complex process of fluidization of the partially consolidated mud is examined theoretically and experimentally. Experiments were made in a wave-flume using artificial clay. The motion of fluid mud is visually distinguished from the lower stable layer using colored mud, as a tracer. The flume experiments indicate that depth of fluidized mud layer increases by applying higher wave heights or decreasing consolidation period as well as increasing test duration. Also, the experimental results show that the fluid mud thickness varies nonmonotonically with wave period.The maximum wave-induced shear stress in the bed at the onset of fluidization that is calculated by an analytical model, assuming that the consolidated mud has a linear elastic behavior before fluidization, is shown to be just larger than the yield strength of the bed at a particular level in the bed. The yield strength of the bed is determined independently with rheological experiments for various water content of the bed. The comparison between the measured fluid mud thickness and the theoretical values show general agreement.

کلیدواژه ها:

fluidization ، wave-flume experiments ، artificial clay ، fluid mud ، wave-induced shear stress ، yield strength of the bed ، rheological experiments