DOI: 10.1002/2017JF004410
Scopus记录号: 2-s2.0-85042163102
论文题名: The Role of Three-Dimensional Boundary Stresses in Limiting the Occurrence and Size of Experimental Landslides
作者: Prancevic J.P. ; Lamb M.P. ; Palucis M.C. ; Venditti J.G.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 1 起始页码: 46
结束页码: 65
语种: 英语
英文关键词: landslide experiments
; landslide size
; shallow landslides
; slope stability
Scopus关键词: experimental study
; hillslope
; landscape evolution
; landslide
; slope stability
; stress
英文摘要: The occurrence of seepage-induced shallow landslides on hillslopes and steep channel beds is important for landscape evolution and natural hazards. Infinite-slope stability models have been applied for seven decades, but sediment beds generally require higher water saturation levels than predicted for failure, and controlled experiments are needed to test models. We initiated 90 landslides in a 5 m long laboratory flume with a range in sediment sizes (D = 0.7, 2, 5, and 15 mm) and hillslope angles (θ = 20° to 43°), resulting in subsurface flow that spanned the Darcian and turbulent regimes, and failures that occurred with subsaturated and supersaturated sediment beds. Near complete saturation was required for failure in most experiments, with water levels far greater than predicted by infinite-slope stability models. Although 3-D force balance models predict that larger landslides are less stable, observed downslope landslide lengths were typically only several decimeters, not the entire flume length. Boundary stresses associated with short landslides can explain the increased water levels required for failure, and we suggest that short failures are tied to heterogeneities in granular properties. Boundary stresses also limited landslide thicknesses, and landslides progressively thinned on lower gradient hillslopes until they were one grain diameter thick, corresponding to a change from near-saturated to supersaturated sediment beds. Thus, landslides are expected to be thick on steep hillslopes with large frictional stresses acting on the boundaries, whereas landslides should be thin on low-gradient hillslopes or in channel beds with a critical saturation level that is determined by sediment size. ©2017. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114756
Appears in Collections: 气候减缓与适应
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作者单位: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, United States; Now at Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland; Now at Department of Earth Science, Dartmouth College, Hanover, NH, United States; Department of Geography, Simon Fraser University, Burnaby, BC, Canada
Recommended Citation:
Prancevic J.P.,Lamb M.P.,Palucis M.C.,et al. The Role of Three-Dimensional Boundary Stresses in Limiting the Occurrence and Size of Experimental Landslides[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(1)