Simulation of velocity and shear stress distributions in granular column collapses by a mesh-free method

Two-dimensional continuum modelling granular column collapse by non-local peridynamics in a mesh-free method with rheology

“…Maintaining the interaction radius r e = 4.0 l constant, the peridynamic horizon was varied as i = 2.2 l, 3.0 l and 4.0 l to simulate the granular column collapse with the aspect ratio a = 1.25 (H = 0.05 m and L = 0.08 m in figure 2). Figure 3 illustrates the free surface profiles at t = 0.12 s, 0.22 s and 0.42 s, calculated by using different peridynamic horizons, which were compared with the experimental measurements (Xu et al 2017). Generally, the free surface profiles using different peridynamic horizons were close to each other, and in good agreement with the experimental results.…”

“…In the simulations, the free surface evolution in the granular column collapse is compared with the experimental observations, with the focus on the free surface and velocity variations in the solid-like state. The simulation is also compared with the previous local modelling without incorporation of peridynamics (Xu et al 2017;Xu et al 2019). This illustrates that peridynamics in the mesh-free method can reproduce the free surface and internal motion in both the fluid-like and solid-like states in the granular flow.…”

“…Xu & Jin (2016b) proposed a mesh-free method by incorporating the μ(I) rheology into the weakly-compressible moving particle semi-implicit method (WC-MPS) to simulate the granular column collapse. They also compared the free-surface profile and velocity distributions with the experimental observations and provided an in-depth discussion on the stress distribution in the flow (Xu et al 2017). The intermediate dense regime in the collapse could be reflected in their simulations.…”

Modeling Two‐Phase Debris Flows With Grain‐Fluid Separation Over Rugged Topography: Application to the 2009 Hsiaolin Event, Taiwan

“…Concerning the erosion/deposition process, it should be noted that the simultaneous release of the whole moving mass with uniform velocity along the flow thickness adopted in the simulation of Hsiaolin event is an extreme condition. Both numerical investigation and laboratory experiments on collapses of granular columns (e.g., Crosta et al, ; Lajeunesse et al, ; Lube et al, ; Xu et al, ) point out the existence of an evolving failure surface at the initiation stage. Hence, the release condition is often the first challenge when numerical simulation is performed for experimental validation, and some specific manipulation is therefore introduced for the initial condition, such as a slightly deformation or linear velocity distribution in the downslope direction (cf.…”

Viscous Elastoplastic SPH Model for Long-Distance High-Speed Landslide

“…While for researches focus on propagation of granular avalanche, a number of researchers still use classical Bingham rheology [Huang et al (2012); Hu et al (2015)]. Some models begin to employ μ(I) rheology borrowed from dense granular flow theory [Pahar and Dhar (2017); Xu et al (2017)]. Until now, there are very few models able to describe the behavior of granular avalanche at both initiation phase and propagation phase.…”