Fluidization Process in Submarine Landslides: Physical and Numerical Considerations: Fid-Bau Portal

Fluidization Process in Submarine Landslides: Physical and Numerical Considerations

Jeong, Sueng Won / Locat, Jacques / Leroueil, Serge / Robert, Jean-Loup

Fluidization processes in submarine landslides were studied by physical and numerical means. To examine soil-water interactions in the fluidization process, the computer axial tomography (CAT)-scan imaging techniques and laboratory vanes were utilized with a focus on the transition from failure to post-failure. Based on the results that were obtained from the scanning images and laboratory vane tests after the process of water infiltration into the soil sample, it appears that a gradual decrease in shear strength is unavoidable with increasing water content in a shear zone. From the numerical results, which were based on the dam-break problem using the transport equation coupled with the Navier-Stokes equation, if the slide is assumed to be initially unstable, a possible transition of fluidization processes that are dependent upon a change in density occurs. The density of the mud decreases with time during the flow at the interface between mud and water. The upper part of the mud pushes the lower part of the mud and then induces a rotation of mud that moves substantial distances. These results emphasize the importance of the soil-water interaction, the need for sediment rheology and the influence of the water circulation on the motion of the landslide.