Effects of Barrier Stiffness on Debris Flow Dynamic Impact—II: Numerical Simulation

Abstract

The destructive and impactful forces of debris flow commonly causes local damage to engineering structures. The effect of a deformable barrier on the impact dynamics is important in engineering design. In this study, a flow–structure coupled with Smoothed Particle Hydrodynamics model was presented to investigate the effects of barrier stiffness on the debris impact. A comparison of the results of physical tests and simulation results revealed that the proposed smoothed particle hydrodynamics model effectively reproduces the flow kinematics and time history of the impact force. Even slight deflections of the deformable barrier lead to obvious attenuation of the peak impact pressure. Additionally, deformable barriers with lower stiffness tend to deform more downstream upon loading, shifting the deposited sand toward the active failure mode and generating less static earth pressure. When the debris flow has a higher frontal velocity, the impact force on the barrier is dominated by the dynamic component and there is an appreciable effect of the stiffness of the deformable barrier on load attenuation.