JpGU-AGU Joint Meeting 2020

Presentation information

[E] Poster

H (Human Geosciences ) » H-DS Disaster geosciences

[H-DS09] Landslides and related phenomena

convener:Masahiro Chigira(Disaster Prevention Research Institute, Kyoto University), Fumitoshi Imaizumi(Faculty of Agriculture, Shizuoka University), Gonghui Wang(Disaster Prevention Research Institute, Kyoto University)

[HDS09-P10] Analytical solutions for submarine avalanche entraining/detraining process

*Yi Ping Lu1, Chi-Yao Hung1 (1.National Chung Hsing University)

Landslides, debris flows, and submarine avalanches are the geophysical examples that alter their volume and travel distance by entraining or detraining granular material at the base. Here, we focus on the entraining/detraining process of submarine landslides. We propose a depth-averaged model using conservation equations for mass, momentum, and kinetic energy. We assume a linearized mu(I) rheology and Coulomb friction law along the side boundary. To obtain the analytical solution, we simplify the model to become a simple nonlinear diffusion equation. Also, a scaling analysis is applied to derive the validity of our simplified model. To check the simplification, we use the HLL scheme and finite volume numerical method to solve the full equation. To verify the model, we propose a new submarine dam break experiment. The experiment is conducted with a new Refractive-Index-Matching (RIM) material. The motion of the granular is monitored with a high-speed camera, and the velocity field can be obtained with Particle Tracking Velocimetry (PTV) method. In the end, we compare the numerical simulation, the analytical solution, and the experimental measurement.