Internal Erosion of Kaolin

Contribution of the transport of suspended particles to the internal erosion in soils. Particle migration in porous media

Revue européenne de génie civil ◽

10.3166/regc.11.493-506 ◽

2007 ◽

Vol 11 (4) ◽

pp. 493-506

Author(s):

Ahmed Benamar ◽

Nasr-Dine Ahfir ◽

Abdellah Alem ◽

Huaqing Wang

Keyword(s):

Porous Media ◽

Suspended Particles ◽

Particle Migration ◽

Internal Erosion

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INTERNAL EROSION OF VOLCANIC COARSE GRAINED SOILS AND ITS EVALUATION

International Journal of Geomate ◽

10.21660/2017.38.70411 ◽

2017 ◽

Vol 13 (38) ◽

Cited By ~ 2

Author(s):

Dao Minh Hieu

Keyword(s):

Internal Erosion ◽

Coarse Grained

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Electromagnetic profiling of Owena Dam, Southwestern Nigeria, using very-low-frequency radio fields

Materials and Geoenvironment ◽

10.1515/rmzmag-2016-0021 ◽

2016 ◽

Vol 63 (4) ◽

pp. 237-250 ◽

Cited By ~ 1

Author(s):

Cyril Okpoli ◽

Raphael Tijani

Keyword(s):

Low Frequency ◽

Soil Mass ◽

Internal Erosion ◽

Dam Failure ◽

Real Component ◽

Southwestern Nigeria ◽

Very Low Frequency ◽

Embankment Dams ◽

Fractured Zones ◽

Basement Structures

AbstractVery low frequency (VLF) was used to assess variations in overburden composition, bedrock lithology and the concealed basement structures within the bedrock of Owena Dam in Igbara-Oke of the Precambrian Basement Complex of Southwestern Nigeria. Five VLF-electromagnetic (EM) traverses were occupied at 5 m intervals. The VLF normal and filtered real component anomalies identify major geological interfaces suspected to be faults/fractured zones. The points of crossover between the real and imaginary components delineate the fractured zones, which were identified as areas of possible seepage (piping and sloughing). The internal erosion (permeability) of soil mass eventually leads to the formation of an open conduit in the soil, which may lead to failure of the embankment/dam. The fractured zones are suspected to be present at all traverses. In total, 21 fractured zones were identified along the dam embankment, with the deepest occurrence at Traverse 5. These seepage zones cause heterogeneity in the subsurface composition, which could lead to dam failure. The result of the study suggests that VLF is an adequate method of monitoring seepages in embankment dams.

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Dam Breach Simulation with the Material Point Method

Computation ◽

10.3390/computation9020008 ◽

2021 ◽

Vol 9 (2) ◽

pp. 8

Author(s):

Chendi Cao ◽

Mitchell Neilsen

Keyword(s):

Material Point Method ◽

Mixture Theory ◽

Material Point ◽

Point Method ◽

Internal Erosion ◽

Dam Breach ◽

New Model ◽

Hencky Strain ◽

The Impact ◽

Soil And Water

Dam embankment breaches caused by overtopping or internal erosion can impact both life and property downstream. It is important to accurately predict the amount of erosion, peak discharge, and the resulting downstream flow. This paper presents a new model based on the material point method to simulate soil and water interaction and predict failure rate parameters. The model assumes that the dam consists of a homogeneous embankment constructed with cohesive soil, and water inflow is defined by a hydrograph using other readily available reach routing software. The model uses continuum mixture theory to describe each phase where each species individually obeys the conservation of mass and momentum. A two-grid material point method is used to discretize the governing equations. The Drucker–Prager plastic flow model, combined with a Hencky strain-based hyperelasticity model, is used to compute soil stress. Water is modeled as a weakly compressible fluid. Analysis of the model demonstrates the efficacy of our approach for existing examples of overtopping dam breach, dam failures, and collisions. Simulation results from our model are compared with a physical-based breach model, WinDAM C. The new model can capture water and soil interaction at a finer granularity than WinDAM C. The new model gradually removes the granular material during the breach process. The impact of material properties on the dam breach process is also analyzed.

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Note: DEM investigations of internal erosion: Grain transport in the light of micromechanics

International Journal for Numerical and Analytical Methods in Geomechanics ◽

10.1002/nag.2933 ◽

2019 ◽

Vol 43 (5) ◽

pp. 1140-1140

Keyword(s):

Internal Erosion

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Dynamic Modeling of Channel Formation During Fluid Injection Into Unconsolidated Formations

SPE Journal ◽

10.2118/173891-pa ◽

2015 ◽

Vol 20 (04) ◽

pp. 689-700 ◽

Cited By ~ 5

Author(s):

S.. Ameen ◽

A. Dahi Taleghani

Keyword(s):

Preferential Flow ◽

Volume Fraction ◽

Injection Pressure ◽

Internal Erosion ◽

Fluid Injection ◽

Critical Threshold ◽

Model Parameters ◽

Flow Paths ◽

Preferential Flow Paths ◽

Stress Changes

Summary Injectivity loss is a common problem in unconsolidated-sand formations. Injection of water into a poorly cemented granular medium may lead to internal erosion, and consequently formation of preferential flow paths within the medium because of channelization. Channelization in the porous medium might occur when fluid-induced stresses become locally larger than a critical threshold and small grains are dislodged and carried away; hence, porosity and permeability of the medium will evolve along the induced flow paths. Vice versa, flowback during shut-in might carry particles back to the well and cause sand accumulation inside the well, and subsequently loss of injectivity. In most cases, to maintain the injection rate, operators will increase injection pressure and pumping power. The increased injection pressure results in stress changes and possibly further changes in channel patterns around the wellbore. Experimental laboratory studies have confirmed the presence of the transition from uniform Darcy flow to a fingered-pattern flow. To predict these phenomena, a model is needed to fill this gap by predicting the formation of preferential flow paths and their evolution. A model based on the multiphase-volume-fraction concept is used to decompose porosity into mobile and immobile porosities where phases may change spatially, evolve over time, and lead to development of erosional channels depending on injection rates, viscosity, and rock properties. This model will account for both particle release and suspension deposition. By use of this model, a methodology is proposed to derive model parameters from routine injection tests by inverse analysis. The proposed model presents the characteristic behavior of unconsolidated formation during fluid injection and the possible effect of injection parameters on downhole-permeability evolution.

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