A two-phase debris flow model with boulder transport Article

Martinez, C, Garcia-Martinez, R, Miralles-Wilhelm, F. (2011). A two-phase debris flow model with boulder transport . 1(4), 389-402. 10.2495/SAFE-V1-N4-389-402

cited authors

  • Martinez, C; Garcia-Martinez, R; Miralles-Wilhelm, F

authors

abstract

  • We present a quasi three-dimensional numerical model to simulate debris fl ows that considers a continuum non-Newtonian fl uid phase for water and fi ne sediments, and a non-continuum phase for large particles such as boulders. Particles are treated in a Lagrangian frame of reference using the 3D Discrete Element Method. The fl uid phase is implemented in the RiverFLO-2D model, which solves the 2D depth-averaged shallow water equations with the Finite Element Method on a triangular non-structured mesh. The model considers particle-particle and wall-particle collisions, taking into account that particles are immersed in a fl uid and subject to gravity, friction and drag forces. Bingham and Cross rheological models are used for the continuum phase providing very stable results, even in the range of very low shear rates. Results show that Bingham formulation proves better able to simulate the stopping of the fl uid when the applied shear stresses are low. Comparing numerical results with analytical solutions and data from fl ume-experiments demonstrates that the model is capable of replicating the motion of large particles moving in the fl uid fl ow. An application to simulate debris fl ows that occurred in Northern Venezuela in 1999 shows that the model can replicate the main boulder accumulation reported for that event. © 2011 WIT Press.

publication date

  • January 1, 2011

Digital Object Identifier (DOI)

start page

  • 389

end page

  • 402

volume

  • 1

issue

  • 4