Protective effects of baffles with different positions, row spacings, heights on debris flow impact

• Published in: Journal of mountain science Vol. 21; no. 7; pp. 2352 - 2367
• Main Authors: Sun, Xinpo, Chen, Min, Bi, Yuzhang, Zheng, Lu, Che, Chi, Xu, Ao, Tian, Zijian, Jiang, Zheyuan
• Format: Journal Article
• Language: English
• Published: Heidelberg Science Press 01.07.2024
• Subjects: Earth and Environmental Science; Earth Sciences; Ecology; Environment; Geography; Original Article; Protective effect; Debris flow; Discrete element; Baffle
• ISSN: 1672-6316; 1993-0321
• DOI: 10.1007/s11629-024-8658-0

The baffle effectively slowed down debris flow velocity, reduced its kinetic energy, and significantly shortened the distance of debris flow movement. Consequently, they are widely used for protection against natural hazards such as landslides and mudslides. This study, based on the three-dimensional DEM (Discrete Element Method), investigated the impact of different baffle positions on debris flow protection. Debris flow velocity and kinetic energy variations were studied through single-factor experiments. Suitable baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris flow. Subsequently, based on the selected baffle positions and four factors influencing the effectiveness of baffle protection (baffle position ( P ), baffle height ( h ), row spacing ( S r ), and angle of transit area ( α )), an orthogonal design was employed to further explore the optimal arrangement of baffles. The research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their energy. When the baffle is placed in the transit area, the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition area. Similarly, when the baffle is placed in the transit area, the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition area. Through orthogonal experimental range analysis, when the impact on the first row of baffles is used as the evaluation criterion, the importance of each influencing factor is ranked as α > P > S r > h . When the mass of debris flow behind the baffle is regarded as the evaluation criterion, the rank is changed to P > α > S r > h . The experimental simulation results show that the optimal baffle arrangement is: P 5 , S r =16, α =35°, h =9.