Computational assessment of baffle performance against rapid granular flows

Rapid granular flows are one of the most catastrophic geo-disasters frequently encountered in mountainous areas. The baffle structure has been demonstrated to be an effective measure for decreasing the destructivity of such geo-disasters. In this paper, a flow-baffle interaction model based on the 3D discrete element method is adopted to assess the baffle performance, hoping to facilitate the optimal design of baffles. A multiple-indicator-based framework, which covers three aspects and six metrics, is proposed and used to thoroughly and quantitatively assess the energy dissipation capacity, deposition regulation function, and failure potential of the baffle structure considering the particle size and baffle shape effect. Results indicate that the particle size significantly affects the baffle performance, and several linear relationships are proposed to account for the effect of the particle size, which may serve to improve engineering structural design. The square baffle performs better than the triangular baffle even though they have identical transverse blockage. Investigation of the patterns of the force chain distribution in granular flows confirms that the flow-baffle interaction is controlled by the evolution of force chains. The particle size and baffle shape effect can be explained by the difference in stability of arches that form during flow-baffle interaction. In addition, the quantification of energy loss due to inelastic contact between particles and baffles reveals that enhanced particle-particle interaction is the dominant energy dissipation mechanism, accounting for more than 80-90% of the total energy loss.

Automated summary

This study evaluates the performance of baffle structures in rapid granular flows using a flow-baffle interaction model, considering the effects of particle size and baffle shape. The results show that particle size is a key factor influencing baffle performance, while enhanced particle-particle interaction is the dominant energy dissipation mechanism.