Debris Flow Impact Mitigation Using Dual Flexible Barriers: Experimental and Numerical Study
DOI:
https://doi.org/10.64862/Keywords:
debris flows, flexible barrier, impact, Flume experimentAbstract
Debris flows pose severe threats to infrastructure and lives globally. Multiple flexible barriers offer a sustainable alternative to single rigid structures by progressively retaining and decelerating debris flows. This study investigates dynamic interactions between debris flows and dual flexible barriers through physical flume tests and numerical back-analysis. A 9.0 m³ debris flow impacts two flexible barriers in a 28-m flume, revealing mechanisms like frontal impact, runup rollback, overflow, and landing. The numerical model captures key kinematics and stress evolution. Results show the first barrier significantly reduces peak impact pressure on the second barrier, enhancing design efficacy for multi-barrier systems.
References
Froude, M.J. and Petley, D.N., 2018. Global fatal landslide occurrence from 2004 to 2016. Natural hazards and earth system sciences, 18(8), pp.2161–2181. https://doi.org/10.5194/nhess-18-2161-2018.
Kramer, M., Schultes, S., Sodnik, J., Kozmus Trajkovski, K., & Bezak, N. (2025). Impact of flexible net barriers on torrential processes under different hydrological conditions, including the extreme flood of August 2023 in Slovenia. Nat Hazards. https://www.doi.org/10.1007 /s11069-025-07673-7.
Lam, H.W.K., Sze, E.H.Y., Wong, E.K.L., Poudyal, S., Ng, C.W.W., Chan, S.L. and Choi, C.E., 2022. Study of dynamic debris impact load on flexible debris-resisting barriers and the dynamic pressure coefficient. Canadian Geotechnical Journal, 59(12), pp.2102–2118. https://doi.org/10.1139/cgj-2021-0325.
Ng, C.W.W., Choi, C.E., Liu, H., Poudyal, S. and Kwan, J.S.H., 2020. Design Recommendations for Single and Dual Debris Flow Barriers with and Without Basal Clearance. In: K. Sassa, M. Mikoš, S. Sassa, P.T. Bobrowsky, K. Takara and K. Dang, eds. Understanding and Reducing Landslide Disaster Risk, ICL Contribution to Landslide Disaster Risk Reduction. Switzerland: Springer International Publishing. pp.33–53. https://doi.org/ 10.1007/ 978-3-030-60196-6_2.
Ng, C.W.W., Li, Z., Poudyal, S., De Silva, W.A.R.K., Bhatta, A. and Liu, H., 2024. Experimental and SPH Modeling of Debris-Flow Impact on Dual Rigid Barriers with Deflector. Journal of Geotechnical and Geoenvironmental Engineering, 150(5), p.04024023. https://doi.org/10.1061/JGGEFK.GTENG-12192.
NILIM, 2022. Technical guideline for Establishing Sabo Master Plan against Debris Flow and Driftwood. [Technical Note of NILIM] Japan: National Institute for Land and Infrastructure Management, Sabo Planning Division, Sabo Department. p.85.
Poudyal, S., 2024. Mechanisms and design of debris flow impact on multiple flexible barriers. [PhD Thesis] The Hong Kong University of Science and Technology.
SWCB, 2019. Soil and Water Conservation Handbook. [online] Soil and Water Conservation Bureau, Taiwan: Soil and Water Conservation Bureau. p.523. Available at: <http://scwb.gov.tw>.
Wendeler, C., Volkwein, A., Roth, A., Herzog, B., Hahlen, N. and Wenger, M., 2008. Hazard prevention using flexible multi-level debris flow barrier. In: INTERPRAEVENT 2008 – Conference Proceedings, Vol.1. INTERPRAEVENT. Austria: Citeseer. pp.547–554.
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