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Title: Effects of density and slope angle on internal erosion in an unsaturated clayey sand slope
Soil piping (concentrated leak erosion) is a major contributor to soil erosion in many parts of the world, and collapse of eroded pipes can result in the formation of gullies and sinkholes or trigger slope instability. Despite these significant impacts, there is little understanding of factors controlling pipe collapse, and how water within the pipe influences moisture levels within a slope. In this study, physical models were employed on unsaturated model slopes with pre-formed macropores to investigate how soil properties, pipe characteristics, and hydraulic conditions govern internal erosion processes and slope stability. Experiments simulated shallow field conditions (0.45 m overburden) using 4 mm and 12 mm pipes to establish preferential flow paths, while varying model parameters including initial compaction moisture content and density, pipe condition (absent, closed, or open), slope angle, and model width. Volumetric water content sensors monitored moisture evolution, while cameras captured slope responses to subsurface flow. Results demonstrate that initial compaction conditions (water content and density), pipe size, hydraulic connectivity, and pipe condition control internal erosion processes and slope stability.  more » « less
Award ID(s):
2047402
PAR ID:
10591608
Author(s) / Creator(s):
; ;
Publisher / Repository:
Designsafe-CI
Date Published:
Subject(s) / Keyword(s):
Internal erosion Landslides Unsaturated soil mechanics Physical models Concentrated leak erosion
Format(s):
Medium: X
Institution:
Auburn University Geotechnical Laboratory
Sponsoring Org:
National Science Foundation
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