A Comparative SPH Analysis of Interaction Between Viscous Debris Flow and Two Types of Barriers with Basal Clearance

Debris flows are a type of geophysical flow and are known as one of the most destructive geohazards. To control and mitigate damage to residential areas and infrastructure downstream, rigid barriers are installed along the flow path to dissipate the momentum and energy of the flow. While basal clearance and curved barriers have shown potential for granular flows, their combined application to viscous debris flows has remained unstudied. Therefore, this study aims to incorporate the advantages of barriers with basal clearance and curved geometries for application to viscous debris flows. To this end, a series of seven numerical simulations were performed using the smoothed particle hydrodynamics (SPH) method in LS-DYNA[1] to compare the performance of vertical and curved barriers with a basal clearance in the second row. The results indicate that curved barriers enhance the interaction process through rebounding, reducing the maximum kinetic energy by 59% in the most effective scenario (CNB2) compared to free flow conditions. Consequently, a system featuring a curved barrier in the first row and a narrow basal clearance in the second row was found to be the most practical. Furthermore, a single curved barrier reduced momentum by 16% more than a single vertical wall, performing similarly to dual vertical systems. Finally, it is noted that where site constraints or costs preclude two-barrier systems, a well-designed single curved barrier offers a viable alternative. [1] https://lsdyna.ansys.com/