Speaker
Description
Debris flows are among the most destructive geohazards owing to their high impact force, complex rheology, and pronounced scale-dependent behavior. In practical hazard mitigation, dual or multiple barriers are frequently installed in series to intercept large-volume debris flows through a cascading process of momentum reduction and energy dissipation. Although large-scale physical experiments have provided valuable insights into debris-flow-barrier interaction, the fundamental mechanisms governing overflow and impact within multi-barrier systems remain insufficiently understood. In this study, the interaction between debris flow and dual barriers is investigated numerically using a graphics processing unit (GPU)-accelerated smoothed particle hydrodynamics (SPH) framework, in which the granular phase is described by a Bingham-type constitutive model. The numerical results demonstrate that the adopted framework can reproduce the key dynamic features reported in large-scale experiments, including jet-like overflow, the temporal evolution of overflow distance, and rebound following impact. The simulations further suggest that the principal role of debris-resisting barriers may be to intercept the highly energetic flow front, whereas a substantial proportion of the energy carried by the subsequent flow mass is dissipated through internal shearing and progressive flow--barrier interaction. These findings highlight the potential of GPU-accelerated SPH for investigating debris-flow impact mechanisms and supporting the rational design of dual-barrier mitigation systems.