Abstract
Using a small flume, a series of tests was conducted to trigger rainfall-induced landslides. Based on monitoring of sliding distance and pore pressures, the process of pore-pressure generation in relation to sliding distance was examined. By performing tests on sands of different grain sizes (silica sand no. 7 (D 50= 0.14 mm) and no. 8 (D 50= 0.057 mm)) at different initial dry densities or different thicknesses, the effects of these factors on pore-pressure generation and failure behavior of a landslide mass were analyzed. Results from tests of different initial densities showed that for each sample there was an optimal density index, at which the pore pressure build-up after failure reached its maximum value. This optimal density index varied with the thickness of sample and the grain size of samples. Moreover, observed failure phenomena showed that the failure mode also depended greatly on the grain size and sample thickness. In fact, flowslides were initiated in the tests on finer silica sand (no. 8), whereas retrogressive sliding occurred in the tests on silica sand no. 7. Results of tests on mixtures of silica sand no. 8 with different contents of loess by weight showed that the existence of fine-particle soil (loess) could significantly change the flow behavior of a landslide mass during motion: the flow behavior of soils with 20 and 30 percent loess was different from these two silica sands and the mixture with 10 percent loess, showing greater velocity without deceleration. This suggests the existence of a mechanism that maintains high pore pressures during motion for these soils. In addition, by rotating saturated samples in a double-cylinder apparatus, a mechanism was examined in which pore pressure in saturated soils during motion was maintained. The results showed that the pore pressure of the saturated mixture increased with velocity because of the “floating” of sand grains that accompanied the movement for each test. In addition, the sample with finer grain sizes or greater fine-particle (loess) contents floated more easily, and high pore pressure could be maintained during motion. The floating ratios of grains reached a high value (>0.85) at a very slow velocity for samples with 20 and 30 percent loess. Based on these test results, it is concluded that grain size and fine-particle contents can have a significant impact on the mobility of rainfall-induced landslides.
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References
Anderson SA, Sitar N (1995) Analysis of rainfall-induced debris flow. J Geotech Eng-Asce 121(7):544–552
Bishop AW (1967) Progressive failure-with special reference to the mechanism causing it. In: Proceedings of Geotechnical Conference, Oslo, Norway, 2, pp 142–150
Bishop AW (1973) The stability of tips and spoil heaps. Q J Eng Geol 6:335–376
Brand EW (1981) Some thoughts on rainfall induced slope failures. In: Proceedings of 10th International Conference on Soil Mechanics and Foundation Engineering, pp 373–376
Brenner RP, Tam HK, Brand EW (1985) Field stress path simulation of rain-induced slope failure. In: Proceedings of 11th International Conference on Soil Mechanics and Foundation Engineering, 2, pp 373–376
Broscoe AJ, Thomson S (1969) Observation on an alpine mudflow, Steele Creek, Yukon. Can J Earth Sci 6:219–229
Campbell CS (1990) Rapid granular flows. Annu Rev Fluid Mech 22:57–92
Casagrande A (1936) Characteristics of cohesionless soils affecting the stability of slopes and earth fills. Journal of the Boston Society of Civil Engineers, reprinted in Contributions to Soil Mechanics, 1925 to 1940, Boston Society of Civil Engineers, pp 257–276
Casagrande A (1971) On liquefaction phenomenon. Géotechnique 21(3):197–202
Castro G (1969) Liquefaction of sands. Ph.D. Thesis, Harvard University, Cambridge, Massachusetts
Castro G, Poulos SJ (1977) Factors affecting liquefaction and cyclic mobility. J Geotech Eng-ASCE 103:501–516
Curry RR (1966) Observation of alpine mudflows in the Tenmile Range, central Colorado. Geol Soc Am Bull 77:771–776
Eckersley JD (1985) Flowslides in stockpiled coal. Eng Geol 22: 13–22
Eckersley JD (1986) The institution and development of slope failures with particular reference to flowslides. PhD thesis, James Cook University of North Queensland
Eckersley JD (1990) Instrumented laboratory flowslides. Géotechnique 40(3):489–502
Fryxell FM, Horberg L (1943) Alpine mudflows in Grand Teton National Park, Wyoming. Geol Soc Am Bull 54:457–472
Hird HH, Hassona FAK (1990) Some factors affecting the liquefaction and flow of saturated sands in laboratory tests. Eng Geol 28:149–170
Ishihara K (1993) Liquefaction and flow failure during earthquakes. Géotechnique 43(3):349–451
Ishihara K, Okusa S, Oyagi N, Ischuk A (1990) Liquefaction-induced flowslide in the collapsible loess deposit in Soviet Tajik. Soils and Foundations 30(4):73–89
Iverson RM (1997) The physics of debris flows. Rev Geophys 35(3):245–296
Iverson RM, LaHusen RG (1989) Dynamic pore-pressure fluctuations in rapidly shearing granular materials. Science 246: 796–799
Iverson RM, Reid ME, LaHusen RG (1997) Debris-flow mobilization from landslides. Annu Rev Earth Planet Sci 25:85–138
Iverson RM, Reid ME, Iverson NR, LaHusen RG, Logan M, Mann JE, Brien DL (2000) Acute sensitivity of landslide rates to initial soil porosity. Science 290:513–516
Kramer KL (1988) Triggering of liquefaction flow slides in coastal soil deposits. Eng Geol 26:17–31
Kramer KL, Seed HB (1988) Initiation of soil liquefaction under static loading conditions. J Geotech Eng-ASCE 114:412–430
Major JJ, Iverson RM (1999) Debris-flow deposition: Effects of porefluid pressure and friction concentrated at flow margins. Geol Soc Am Bull 111(10):1424–1434
Ogawa S (1978) Multitemperature theory of granular materials. In: Proceedings of U.S.-Japan Seminar on Continuum-Mechanics and Statistical Approaches to the Mechanics of Granular Materials, Gukujutsu Bunken Fukyukai, Tokyo, pp 208–217
Sassa K (1972) Analysis on slope stability-I: mainly on the basis of the indoor experiments using the standard sand produced in Toyoura, Japan. J Jpn Soc Erosion Control Eng 25(2):5–17 (in Japanese with English abstract)
Sassa K (1974) Analysis on slope stability-II: Mainly on the basis of the indoor experiments using the standard sand produced in Toyoura, Japan. J Jpn Soc Erosion Control Eng 26(3):8–19 (in Japanese with English abstract)
Sassa K (1984) The mechanism starting liquefied landslides and debris flows. In: Proceedings of 4th International Symposium on Landslides, Toronto, June, 2, pp 349–354
Sassa K (1985) The mechanism of debris flows. In: Proceedings of XI International Conference on Soil Mechanics and Foundation Engineering, San Francisco, 3, pp 1173–1176
Sassa K (1988a) Motion of landslides and debris flows-prediction of hazard area. In: Report for Grant-in-Aid for Scientific Research by Japanese Ministry on Education, Science and Culture (Project No. 61480062), pp 1–15
Sassa K (1988b) Geotechnical model for the motion of landslides. In: Special Lecture of 5th International Symposium on Landslides, “Landslides”, 10–15 July, 1, pp 37–55
Sassa K (1996) Prediction of earthquake induced landslides. In: Proceedings of 7th International Symposium on Landslides, A.A. Balkema, Trondheim, 17–21 June, 1, 115–132
Sassa K (1998a) Recent urban landslide disasters in Japan and their mechanisms. In: Proceedings 2nd International Conference on Environmental Management, “Environmental Management”, 1, pp 47–58
Sassa K (1998b) Mechanisms of landslide triggered debris flow. In: Sassa K (ed) Environmental forest science: Proceedings of IUFRO Div. 8 Conference, Kyoto, Kluwer Academic Publisher, pp 471–490
Sassa K (2000) Mechanism of flows in granular soils. In: Proceedings of the International Conference of Geotechnical and Geological Engineering, GEOENG2000, Melbourne, 1, pp 1671–1702
Sassa K, Takei A (1977a) Consider vertical subsidence in slope unstabilization — I: Stress fall phenomenon and bearing power of the sides. J Jpn Landslide Soc 14(2):19–26 (in Japanese with English abstract)
Sassa K, Takei A (1977b) Consider vertical subsidence in slope unstabilization — II: Some examples in the field. J Jpn Landslide Soc 14(3):7–14 (in Japanese with English abstract)
Seed HB (1966) Landslides during earthquakes due to soil liquefaction. J Soil Mech Found Div-ASCE 94(5):1055–1122
Seed HB (1979) Soil liquefaction and cyclic mobility evaluation for level ground during earthquakes. J Geotech Eng-ASCE 105:201–255
Sidle RC, Swanston DN (1982) Analysis of a small debris slide in coastal Alaska. Can Geotech J 19:167–174
Sitar N, Anderson SA, Johnson KA (1992) Conditions leading to the initiation of rainfall-induced debris flows. Geotech. Engrg. Div. Specialty Conference: Stability and Perf. of slopes and Embankments-II, ASCE, New York, pp 834–839
Sladen JA, D’Hollander RD, Krahn J (1985) The liquefaction of sands, a collapse surface approach. Can Geotech J 22:564–578
Spence KJ, Guymer I (1997) Small-scale laboratory flowslides. Géotechnique 47(5):915–932
Terzaghi K (1950) Mechanism of landslides. In: Paige S (ed) Application of geology to engineering practice (Berkey Volume) Geological Society of America, New York, pp 83–123
Terzaghi K (1956) Varieties of submarine slope failures. In: Proceedings of 8th Texas Conference on Soil Mechanics and Foundation Engineering, pp 1–41
Thevanayagam S (1998) Effects of fines and confining stress on undrained shear strength of silty sands. J Geotech Geoenviron 124(6):479–491
Vallejo LE, Mawby R (2000) Porosity influence on the shear strength of granular material-clay mixtures. Eng Geol 58:125–136
Wang G, Sassa K (2001) Factors affecting rainfall-induced flowslides in laboratory flume tests. Géotechnique 51(7):587–599
Wang G, Sassa K (2003) Pore pressure generation and movement of rainfall-induced landslides: effects of grain size and fine particle content. Engineering geology 69:109–125
Wang GH, Sassa K, Fukuoka H, Wang FW (1998) Study on the excess pore pressure generation in laboratory-induced-landslides. In: Moore DP, Hungr O (eds) Proceedings of 8th Congress of IAEG, Vancouver, Balkema, Rotterdam, 6, pp 4237–4244
Youd TL, Gilstrap SG (1999) Liquefaction and deformation of silty and fine-grained soils. In: Proceedings of 2nd International Conference on Earthquake Geotechnical Engineering, Lisbon, Portugal, 3, pp 1013–1020
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Wang, G., Sassa, K. (2007). On the Pore-pressure Generation and Movement of Rainfall-induced Landslides in Laboratory Flume Tests. In: Sassa, K., Fukuoka, H., Wang, F., Wang, G. (eds) Progress in Landslide Science. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-70965-7_12
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