Abstract
This paper reports an investigation on the performance of ethylene-vinyl acetate (EVA) foam when used as a cushion layer for rigid barriers used to resist debris flow. Large-scale pendulum impact tests were conducted to study the effects of layer thickness on cushion performance under six successive impacts. Results show that for the first impact at 70 kJ, the peak contact force with the EVA foam thickness of 500 mm is about twice larger compared to that of 1000 mm. Results also reveal that the cushion mechanism of elastic collapse of cell walls in the EVA foam results in peak contact forces and maximum transmitted loads that are up to 30 and 50% lower compared to gabions for the first impact at 70 kJ, respectively. The elastic behavior of EVA foam provides consistent cushioning efficiency. Furthermore, EVA foam is found to be susceptible to degradation by ultraviolet light so that a suitable coating layer is required for outdoor use. Polyurea was identified as a suitable coating material and a small-scale coating trial was performed to confirm this. Findings presented in this paper will have direct implications on the future design of cushion layers for rigid barriers used to intercept debris flows.
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References
ASTM (2005) Standard practice for fluorescent UV exposure of plastics. ASTM D4329-05. ASTM International, West Conshohocken, Pennsylvania, USA
ASTM D1621-16 (2010), Standard Test Method for Compressive Properties of Rigid Cellular Plastics, ASTM International, West Conshohocken, PA.
ASTM (2014) Standard test method for apparent density of rigid cellular plastics. ASTM D1622/D1622M-14. ASTM International, West Conshohocken, Pennsylvania, USA
ASTM (2015) Standard test methods for rubber property—durometer hardness. ASTM D2240-15. ASTM International, West Conshohocken
ASTRA (2008) Einwirkungen infolge Steinschlags auf Schutzgalerien, Richtlinie (Effects of Rockfall on Protection Galleries, Guideline). Bundesamt für Strassen ASTRA (Federal Roads Office), Switzerland (in German)
BSI (1998) Plastics—ethylene/vinyl acetate copolymer (EVAC) thermoplastics—determination of vinyl acetate content. BS EN ISO 8985:1998. British Standards Institution, London
Carey NL, Myers JJ (2012) Blast testing of three types of panels with external strengthening systems. In: Dynamic Behavior of Materials, Volume 1: Proceedings of the 2012 Annual Conference on Experimental and Applied Mechanics, Springer, p. 417–424
Choi KY, Cheung RWM (2013) Landslide disaster prevention and mitigation through works in Hong Kong. Journal of Rock Mechanics and Geotechnical Engineering. 5(5):354–365
Choi H, Toutanji HA, Gilbert JA, Alldredge DJ (2013) Impact resistance of polyurea-coated high-performance cementitious composites. J Mater Civ Eng 25(12):1984–1989
Choi CE, Ng CWW, Law RPH, Song D, Kwan JSH, Ho KKS (2014) Computational investigation of baffle configuration on impedance of channelized debris flow. Can Geotech J 52(2):182–197
Gray JMNT, Chugunov VA (2006) Particle-size segregation and diffusive remixing in shallow granular avalanches. Journal of Fluid Mechanics 569(25):365–398
Gibson LJ, Ashby MF (1997) Cellular solids—structures and properties, 2nd edition. Cambridge University Press, Cambridge
Huang HP, Yang KC, Lai SW (2007) Contact force of debris flow on filter dam. Geophys Res Abstract 9:03218
Hungr O, Morgan GC, Kellerhals R (1984) Quantitative analysis of debris torrent hazards for design of remedial measures. Can Geotech J 21(4):663–677
Hungr O, Leroueil S, Picarelli L (2014) The Varnes classification of landslide types, an update. Landslides 11(2):167–194
Jan C-D, Chen C-L (2005) Debris flows caused by Typhoon Herb in Taiwan. In: Jakob M, Hungr O (eds) Debris-flow hazards and related phenomena. Springer, Berlin, pp 539–563
Johnson KL (1985) Contact mechanics. Cambridge University Press, London
JRA (2000) Guideline for rockfall counter measure: Maruzen
Kanji MA, Cruz PT, Massad F (2008) Debris flow affecting the Cubatão oil refinery, Brazil. Landslides 5(1):71–82
Kostopoulus V, Markopoulos YP, Giannopoulos G, Vlachos DE (2002) Finite element analysis of impact damage response of composite motorcycle safety helmets. Composites, Part B 33:99–107
Kwan JSH (2012) Supplementary technical guidance on design of rigid debris-resisting barriers. GEO report no. 270. Geotechnical Engineering Office, Hong Kong
Kwan JSH, Koo RCH, Ng CWW (2015) Landslide mobility analysis for design of multiple debris-resisting barriers. Can Geotech J 52(9):1345–1359
Lambert S, Gotteland P, Nicot F (2009) Experimental study of the impact response of geocells as components of rockfall protection embankments. Nat Hazards Earth Syst Sci 9(2):459–467
Lambert S, Heymann A, Gotteland P, Nicot F (2014) Real-scale investigation of the kinematic responses of a rockfall protection embankment. Nat Hazards Earth Syst Sci 14(5):1269–1281
Liu K-F, Jan C-D, Lin PS, Li S-C (2013) Advances of geo-disaster mitigation technologies in Taiwan. In: Progress of geo-disaster mitigation technology in Asia. Springer, Berlin, pp 77–103
Mancarella D, Hungr O (2010) Analysis of run-up of granular avalanches against steep, adverse slopes and protective barriers. Can Geotech J 47(8):827–841
Mizuyama T (1979) Computational method and some considerations on impulsive force of debris flow acting on sabo dams. J Jpn Soc Erosion Control Eng 32(1):40–43 (in Japanese)
Ng CWW, Choi CE, Song D, Kwan JSH, Koo RCH, Shiu HYK, Ho KKS (2015) Physical modeling of baffles influence on landslide debris mobility. Landslides 12(1):1–18
Ng CWW, Choi CE, Su AY, Kwan JSH, Lam C (2016) Large-scale successive boulder impacts on a rigid barrier shielded by gabions. Can Geotech J 53(10):1688–1699
Remaître A, van Asch TWJ, Malet J-P, Maquaire O (2008) Influence of check dams on debris-flow run-out intensity. Nat Hazards Earth Syst Sci 8(6):1403–1416
Shima J, Moriyama H, Kokuryo H, Ishikawa N, Mizuyama T (2016) Prevention and mitigation of debris flow hazards by using steel open-type sabo dams. Int J Erosion Control Eng 9(3):135–144
Suda J, Strauss A, Rudolf-Miklau F, Hübl J (2009) Safety assessment of barrier structures. Struct Infrastruct Eng 5(4):311–324
Zhang S, Hungr O, Slaymaker O (1996) The calculation of contact force of boulders in debris flow. In: Du R (ed) Debris flow observation and research. Science Press, Beijing, pp 67–72 (in Chinese)
Acknowledgements
This paper is published with the permission of the Head of the Geotechnical Engineering Office and the Director of Civil Engineering and Development of the Hong Kong Special Administrative Region (SAR) Government. The authors acknowledge the financial support of the Research Grants Council of the Hong Kong SAR Government through the theme-based research grant no. T22-603/15-N. The authors are grateful for the support by the HKUST Jockey Club Institute for Advanced Study.
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Lam, C., Kwan, J.S.H., Su, Y. et al. Performance of ethylene-vinyl acetate foam as cushioning material for rigid debris-resisting barriers. Landslides 15, 1779–1786 (2018). https://doi.org/10.1007/s10346-018-0987-z
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DOI: https://doi.org/10.1007/s10346-018-0987-z