ABSTRACT
The Lagrangian Galerkin finite element method (FEM) is formulated in this paper for simulating general unsteady muddy debris flows, in which the viscoplastic Bingham model is coded. The introduction of lumped mass matrix turns out to be a volume-weighted procedure. The second pass mass-lumping not only facilities an explicit solution, but also automatically releases the continuity constraint. The current numerical model is validated and a substantial agreement is produced in comparison to experimental results. Application to the Lai Ping Road landslide of Hong Kong, July 2, 1997, reasonably simulates the landslide process.
