Journal of Mountain Science

, Volume 14, Issue 3, pp 417–431 | Cite as

Experimental study on the moving characteristics of fine grains in wide grading unconsolidated soil under heavy rainfall



The initiation mechanism of debris flow is regarded as the key step in understanding the debris-flow processes of occurrence, development and damage. Moreover, migration, accumulation and blocking effects of fine particles in soil will lead to soil failure and then develop into debris flow. Based on this hypothesis and considering the three factors of slope gradient, rainfall duration and rainfall intensity, 16 flume experiments were designed using the method of orthogonal design and completed in a laboratory. Particle composition changes in slope toe, volumetric water content, fine particle movement characteristics and soil failure mechanism were analyzed and understood as follows: the soil has complex, random and unstable structures, which causes remarkable pore characteristics of poor connectivity, non-uniformity and easy variation. The major factors that influence fine particle migration are rainfall intensity and slope. Rainfall intensity dominates particle movement, whereby high intensity rainfall induces a large number of mass movement and sharp fluctuation, causing more fine particles to accumulate at the steep slope toe. The slope toe plays an important role in water collection and fine particle accumulation. Both fine particle migration and coarse particle movement appears similar fluctuation. Fine particle migration is interrupted in unconnected pores, causing pore blockage and fine particle accumulation, which then leads to the formation of a weak layer and further soil failure or collapses. Fine particle movement also causes debris flow formation in two ways: movement on the soil surface and migration inside the soil. The results verify the hypothesis that the function of fine particle migration in soil failure process is conducive for further understanding the formation mechanism of soil failure and debris flow initiation.


Wide grading unconsolidated soil Fine particle migration Soil failure Landslide Debris flow initiation Flume test Heavy rainfall 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.



This research was supported by the key international collaborative project of Natural Science Foundation of China (No.41520104002).


  1. Blott SJ, Pye K (2001) GRADISTAT: a grain size distribution and statistics package for the analysis of unconsolidated sediments. Earth surface processes and Landforms 26(11): 1237–1248. DOI: 10.1002/esp.261CrossRefGoogle Scholar
  2. Chen NS, Zhou W, Yang CL, et al. (2010a). The processes and mechanism of failure and debris flow initiation for gravel soil with different clay content. Geomorphology 121(3): 222–230. DOI: 10.1016/j.geomorph.2010.04.017CrossRefGoogle Scholar
  3. Chen ZX, Wang R, Hu MJ, et al. (2010b) Study of content of clay particles for debris flow occurrence in Jiangjia Ravine. Rock and Soil Mechanics 31(7): 2197–2201. (In Chinese)Google Scholar
  4. Cui P (1992a) Studies on condition and mechanism of debris flow initiation by means of experiment. Chinese Science Bulletin 37(9): 759–763.Google Scholar
  5. Cui P (1992b) A study on theoretical methods of forecasting debris flow. In Proceedings of international Symposium on Protection of Habitat against Flood, Debris Flow and Avalanche. pp 307–321.Google Scholar
  6. Cui P, Chen X, Wang Y, et al. (2005) Jiangjia Ravine debris flows in south-western China. Debris-flow hazards and related phenomena. Springer Berlin Heidelberg. pp 565–594.CrossRefGoogle Scholar
  7. Cui P, Guo C, Zhou J, et al. (2014) The mechanisms behind shallow failures in slopes comprised of landslide deposits. Engineering Geology 180: 34–44. DOI: 10.1016/j.enggeo.2014.04.009CrossRefGoogle Scholar
  8. Guo X, Cui P, Li Y, et al. (2016) The formation and development of debris flows in large watersheds after the 2008 Wenchuan Earthquake. Landslides 13(1): 25–37. DOI: 10.1007/s10346-014-0541-6CrossRefGoogle Scholar
  9. Guo X, Cui P, Li Y, et al. (2015) Spatial features of debris flows and their rainfall thresholds in the Wenchuan earthquakeaffected area. Landslides 13(5): 1215–1229. DOI: 10.1007/s10346-015-0608-zCrossRefGoogle Scholar
  10. Hedayat AS, Sloane NJA, Stufken J. (2012) Orthogonal arrays: theory and applications. New York: Springer.Google Scholar
  11. Hu M, Wang R, Shen J (2011) Rainfall, landslide and debris flow intergrowth relation in Jiangjia Ravine. Journal of Mountain Science 8(4): 603–610. DOI: 10.1007/s11629-011-2131-6CrossRefGoogle Scholar
  12. Hu M, Pan H, Wei H, et al. (2013). Landslides & Debris Flows Formation from Gravelly Soil Surface Erosion and Particle Losses in Jangjia Ravie. Journal of Mountain Science 10(6): 987–995. DOI: 10.1007/s11629-012-2526-zCrossRefGoogle Scholar
  13. Iverson R M (1997) The physics of debris flow. Reviews of Geophysics 35(3): 245–296. DOI: 10.1029/97RG00426CrossRefGoogle Scholar
  14. Iverson RM, Reid MA, LaHsen RG (1997) Debris-flow mobilization from landslides. Annual Review of Earth and Planetary Sciences 25: 85–138. DOI: 10.1146/ Scholar
  15. Jakob M, Hungr O, Jakob DM (2005). Debris-flow hazards and related phenomena (Vol. 739). Berlin: Springer.Google Scholar
  16. Kang Z, Zhang S (1980) A preliminary analysis of the characteristics of debris flow. In Proceedings of the International Symposium on River Sedimentation. pp 225–226.Google Scholar
  17. Li Y, Liu J, Hu K, et al. (2012) Probability distribution of measured debris-flow velocity in Jiangjia Gully, Yunnan Province, China. Natural hazards 60(2): 689–701. DOI: 10.1007/s11069-011-0033-0CrossRefGoogle Scholar
  18. Li Y, Su P, Cui P, et al. (2008) A probabilistic view of debris flow. Journal of Mountain Science 5(2): 91–97. DOI: 10.1007/s11629-008-0111-2CrossRefGoogle Scholar
  19. Lu, X, Cui, P (2010a) A study on water film in saturated sand. International Journal of Sediment Research 25(3): 221–232. DOI: 10.1016/S1001-6279(10)60040-6CrossRefGoogle Scholar
  20. Lu X, Cui P, Hu K, Zhang X (2010b) Initiation and development of water film by seepage. Journal of Mountain Science 7(4): 361–366. DOI: 10.1007/s11629-010-2052-9CrossRefGoogle Scholar
  21. Major JJ, Iverson RM (1999) Debris-flow deposition: Effects of pore-fluid pressure and friction concentrated at flow margins. Geological Society of America Bulletin 111(10): 1424–1434.CrossRefGoogle Scholar
  22. Takahashi T (2007) Debris flow: mechanics, prediction and countermeasures, 2nd edition. Netherlands: Taylor & Francis.CrossRefGoogle Scholar
  23. Wang G, Sassa, K (2003) Pore-pressure generation and movement of rainfall-induced landslides: effects of grain size and fine-particle content. Engineering geology 69(1): 109–125. DOI: 10.1016/S0013-7952(02)00268-5CrossRefGoogle Scholar
  24. Wang Z, Li L, Wang R, Hu M (2016) Impact of fine particle content on mode and scale of slope instability of debris flow. Advances in Science and Technology of Water Resources 36(2): 35–41. (In Chinese)Google Scholar
  25. Wang Z, Wang R, Hu M, et al. (2010) Characteristics of gravelly soil and their implications for slope instability in Jiangjiago Ravie. Rock and Soil Mechanics 31(S2): 206–211. (In Chinese)Google Scholar
  26. Wang Z, Wang R, Hu M, et al. (2011) Effects of particle transport characteristics on permeability of soils from Jiangjiagou ravine. Rock and Soil Mechanics 32(17): 2017–2024. (In Chinese)Google Scholar
  27. Xu J, Shang, Y (2006) Influence of permeability of gravel soil on debris landslide stability. Chinese Journal of Rock Mechanics and Engineering 25(11): 2264–2271. (In Chinese)Google Scholar

Copyright information

© Science Press, Institute of Mountain Hazards and Environment, CAS and Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.Department of Civil and Environmental EngineeringHong Kong University of Science and TechnologyClear Water Bay, Hong KongChina
  2. 2.China Merchants Chongqing Communications Research & Design InstituteChongqingChina
  3. 3.Fujian Academy of Building ResearchFujian Key Laboratory of Green Building TechnologyFuzhouChina
  4. 4.Fuzhou UniversityFuzhouChina

Personalised recommendations