State-of-the-art on HYDRAULIC TESTING IN UNSATURATED SOIL · 2005. 7. 8. · Bicalho 1999; Hwang...

11HYDRAULIC TESTING IN UNSATURATED SOILS HYDRAULIC TESTING IN UNSATURATED SOILS -- Experus 2005 Experus 2005 -- TrentoTrento

StateState--ofof--thethe--art art onon

HYDRAULIC TESTING IN UNSATURATED HYDRAULIC TESTING IN UNSATURATED SOILSOIL

F. MASROURI : Institut National Polytechnique de Lorraine, FrancF. MASROURI : Institut National Polytechnique de Lorraine, FranceeK. V. BICALHO : K. V. BICALHO : Federal University of Federal University of EspiritoEspirito Santo, BrazilSanto, Brazil

K. KAWAI : K. KAWAI : Kobe University, JapanKobe University, Japan


1. Water retention characteristicsK. KAWAIK. KAWAI

2. Water and air permeabilities in unsaturated soilsK. V. BICALHOK. V. BICALHO

3. Permeability in unsaturated swelling soilsF. MASROURIF. MASROURI

Outline:Outline:


Water retention characteristicsWater retention characteristics

Degree of saturation Sr (%)

Suc

tion

s (k

Pa)

Res

idua

l deg

ree

of s

atur

atio

n

Air entry value

Water entry valueA

B

C

DE

A'

C'

Main drying curve

Main wetting curve

Scanning curves

Air entry value

Water entry value

INTRODUCTIONINTRODUCTIONWater Retention Characteristic Curve (WRCC)Water Retention Characteristic Curve (WRCC)


WRC DEPENDS ON WRC DEPENDS ON ……Water retention characteristicsWater retention characteristics

(1) Soil properties

(Particle size distribution, Organic matter content, Mineral composition, etc.)

(2) Conditions

(Void ratio, Temperature, Micro structure, Stress state, etc.)

(3) Suction history

(Drying, Wetting, Initial state (ρd, s, Sr))


TESTING FOR WRC TESTING FOR WRC ((1)1)Water retention characteristicsWater retention characteristics

(1) Suction measurement(Filter paper technique, Tensiometer, Psychrometer, Freezing point depression method, etc.)

(2) Indirect method

(Mercury intrusion testing, Air intrusion testing)



(3) Suction Control

Imposs.

Imposs.

Poss

Poss.

Poss

Poss.

Suction history

Good

Fine

Fine

Good

Fine

Fine

Data continuity

0 to 100 (kPa)EvaporationMonitoring

HighCentrifugal forceCentrifuge

0 to 4 (MPa)Osmotic pressureOsmotic

0 to 100 (kPa)Water tableSoil column

4 to 300 (MPa)Salt solutionVapour pressure

0 to 1500 (kPa)Air pressurePressure plate

Suction rangeControl suction with

Technique

TESTING FOR WRC (2)TESTING FOR WRC (2)


MONITORING METHOD

Rassam & Williams (2000)

Toker et al. (2004)




(1) Soil Properties

Particle size distributionGupta & Larson (1979), Ghosh (1980)Araya et al. (1981), Harverkamp & Patlange (1986), Fredlund (1998), Kamiya & Uno (2000), Imre et al. (Experus)

Mineral compositionWilliams et al. (1983), Bilsel & Öncü (Experus), Russo (Experus), Araújo et al. (Experus)

Organic matter content

FACTORS AFFECTING ON WRC (1)FACTORS AFFECTING ON WRC (1)


(2) Conditions


Void ratioFleureau et al. (1993), Kawai et al. (2000), Romero & Vanuat (2000)

TemperatureDuarte et al. (Experus)

StructureCroney & Coleman (1954), Walker et al. (Experus)

Stress states

FACTORS AFFECTING ON WRC (2)FACTORS AFFECTING ON WRC (2)



(1) Experiment

Vachaud & Thony (1971), Toll (1995)

(2) Assuming internal pore structures

Mualem (1974), Nakano (1976), Parlange (1976), Harverkamp & Parlange (1986)

(3) Formulating the derivative

Hanks et al. (1969), Dane & Wierenga (1974), Li (2005)

(4) Similarity between boundary curves and scanning curves

Rojas (2002), Kawai et al. (2002)

EXPRESSION OF HYSTERESIS ON EXPRESSION OF HYSTERESIS ON WRCWRC BYBY


Select an appropriate method for soil properties, site, …

Void ratio strongly influences on WRC.

Temperature, Stress states, are indirect factors, which change void ratio

Quantitative evaluation of WRC by fitting to the empirical equation

To evaluate test results correctly, we have to know how the hysteresis appears

Water retention characteristicsWater retention characteristicsCONCLUDING REMARKSCONCLUDING REMARKS


Unsaturated water and air permeabilityUnsaturated water and air permeability

INTRODUCTION:INTRODUCTION:

All macroscopic properties of porous media are All macroscopic properties of porous media are influenced by the pore structureinfluenced by the pore structure

Permeability (k): macroscopic pore structure parameter Permeability (k): macroscopic pore structure parameter

kk (porous media) depends on the permeating fluid and (porous media) depends on the permeating fluid and the mechanism of permeationthe mechanism of permeation

k is defined by Darcyk is defined by Darcy’’s laws law

Both liquids and gases have been used to measure Both liquids and gases have been used to measure permeabilitiespermeabilities


INTRODUCTION:INTRODUCTION:

kkww (unsaturated soils) : F (soil structure + saturation) (unsaturated soils) : F (soil structure + saturation)

Highly nonlinear and challenging problemHighly nonlinear and challenging problem

Sophisticated experimental and analytical tools are Sophisticated experimental and analytical tools are neededneeded to address the problemto address the problem

Most of the existing laboratory methods yield Most of the existing laboratory methods yield the the kkww –– SSrr (or (or uuww) ) relationshiprelationship

Hysteresis (?)Hysteresis (?)

Unsaturated water permeabilityUnsaturated water permeability



DETERMINATION OF kDETERMINATION OF kww FUNCTIONS: FUNCTIONS:

1.1. Direct methods (steady and unsteady) (*)Direct methods (steady and unsteady) (*)2.2. Indirect methods Indirect methods (empirical, macroscopic and statistical)(empirical, macroscopic and statistical)3.3. Inverse problem solution approach (*)Inverse problem solution approach (*)

(*) (*) Laboratory testingLaboratory testing



DIRECT LABORATORY METHODS : DIRECT LABORATORY METHODS :

1. Steady state1. Steady statea) Constant hydraulic gradient a) Constant hydraulic gradient b) Constant flow rate (flow pump technique) b) Constant flow rate (flow pump technique) c) Centrifuge method c) Centrifuge method

2. Unsteady state2. Unsteady statea) Outflow-inflow methodsb) Instantaneous profile methods


Direct laboratory Direct laboratory –– STEADY STATE methodsSTEADY STATE methods Unsaturated water permeabilityUnsaturated water permeability

1. 1. a) Constant hydraulic gradient a) Constant hydraulic gradient BjerrumBjerrum & & HuderHuder (1957)(1957); Corey 1957Corey 1957 ((Richards 1931)Richards 1931) , Mitchell et al. (1965)

1.1. b) Constant flow rate (flow pump technique) b) Constant flow rate (flow pump technique) Saturated Saturated kkww: Olsen 1966 (fine grained soils), : Olsen 1966 (fine grained soils),

Pane et al. 1983, Olsen & Schiffman, 1983 Pane et al. 1983, Olsen & Schiffman, 1983 AibanAiban & & ZnidarcicZnidarcic 1989 (Constant head 1989 (Constant head vsvs flow pump tests) flow pump tests)

Unsaturated Unsaturated kkww : : ZnidarcicZnidarcic et al. 1991et al. 1991BicalhoBicalho et al. 2000, 2004et al. 2000, 2004

ExperusExperus 2005:2005: BicalhoBicalho, , ZnidarcicZnidarcic & & Ko Ko LikosLikos, Lu & , Lu & WayllaceWayllace


Direct laboratory Direct laboratory –– STEADY STATE methodsSTEADY STATE methods Unsaturated water permeabilityUnsaturated water permeability

1. 1. a) Constant hydraulic gradient a) Constant hydraulic gradient b) Constant flow rate (flow pump technique) b) Constant flow rate (flow pump technique)

Advantages: Advantages:

•• Simplicity in the result analysisSimplicity in the result analysis•• Controls of the stress state variables during the testingControls of the stress state variables during the testing•• FFlow pump provides high level of flow control + short testing tilow pump provides high level of flow control + short testing time me


Direct laboratory Direct laboratory -- STEADY STATE methodsSTEADY STATE methods Unsaturated water permeabilityUnsaturated water permeability

1. c) 1. c) Centrifuge method Centrifuge method ((centrifugal force + steady flow) centrifugal force + steady flow)

HistoryHistory ((Centrifuge modeling)Centrifuge modeling)1930s application to design problems (USSR and USA)1930s application to design problems (USSR and USA)1960s research application in Japan and the UK1960s research application in Japan and the UK1990s extensive instructional application1990s extensive instructional application

NimmoNimmo et al, 1987, 1992; et al, 1987, 1992; ConcaConca & Wright, 1992; Wright et al., 1994 & Wright, 1992; Wright et al., 1994

ExperusExperus 2005:2005: Caputo & Caputo & Nimmo Nimmo (quasi(quasi--steady CM)steady CM)McCartney & Zornberg McCartney & Zornberg


Direct laboratory Direct laboratory –– UNSTEADY STATE methodsUNSTEADY STATE methods Unsaturated water permeabilityUnsaturated water permeability

2. 2. a) Outflowa) Outflow--inflow methodsinflow methodsGardner (1956); Miller & Gardner (1956); Miller & ElrickElrick (1958), (1958), RijtemRijtem (1959), (1959), KunzeKunze & & KirkhamKirkham (1962) and others. (1962) and others. Brace et al. Brace et al. (1968)(1968) (Pulse test)(Pulse test) (very small k values)(very small k values)

2. a.1) 2. a.1) BoltzmannBoltzmann transform methods transform methods ((based on the transformation of Richardbased on the transformation of Richard’’s s equationequation to a to a diffusiondiffusion

equation using equation using BoltzmannBoltzmann’’ss transformation) transformation)

Bruce & Bruce & KluteKlute 1956, 1956, WhislerWhisler et al. 1968, et al. 1968, VachaudVachaud 1968, 1968, AnguloAngulo 19891989

ExperusExperus 2005:2005: BulutBulut, , AubenyAubeny & & LyttonLytton ((UnsatUnsat. Soil . Soil Diffusivity MeasDiffusivity Meas.).)AubenyAubeny, , BulutBulut & & LyttonLytton (laboratory vs. field)(laboratory vs. field)


Direct laboratory Direct laboratory –– UNSTEADY STATE methodsUNSTEADY STATE methods Unsaturated water permeabilityUnsaturated water permeability

2. b) I2. b) Instantaneousnstantaneous profile methods (IPM)profile methods (IPM)

The IPM consists of inducing transient flow in a long cylindricaThe IPM consists of inducing transient flow in a long cylindrical l sample of soil and then measuring the resulting water content sample of soil and then measuring the resulting water content and/or pore water pressure profiles at various time intervalsand/or pore water pressure profiles at various time intervals

Several variations in the method of data analysis have been emplSeveral variations in the method of data analysis have been employedoyed

Measure: Measure: hhpwpw distributions (distributions (ussuss water flow)water flow)Obtain: water content distributionObtain: water content distribution

(from an independently measured or estimated (from an independently measured or estimated WRC)WRC)

History:History:

Richards & Weeks 1953Richards & Weeks 1953Wind 1966 (Wind 1966 (correction of WRC using the outflow data collected)correction of WRC using the outflow data collected)Hamilton et al. 1981, Daniel 1983, Hamilton et al. 1981, Daniel 1983, MeerdinkMeerdink et al. 1996et al. 1996AmraouiAmraoui 19961996



INVERSE PROBLEM SOLUTION APPROACH:INVERSE PROBLEM SOLUTION APPROACH:

Solution of a boundary value problem in which the test Solution of a boundary value problem in which the test results are matched in the numerical analysisresults are matched in the numerical analysis

Obtain WRC and k functions from experimental dataObtain WRC and k functions from experimental data

Known: Known: governing equation + governing equation + initial and boundary conditionsinitial and boundary conditions

Unknown: Unknown: material functions + parametersmaterial functions + parameters

Parameter estimation techniqueParameter estimation technique


Inverse problem solution Inverse problem solution Unsaturated water permeabilityUnsaturated water permeability

History:History:

Soil Mechanics:Soil Mechanics:ZachmanZachman et al. 1981, 1982; Dane & et al. 1981, 1982; Dane & HruskaHruska, 1983, , 1983, ZnidarcicZnidarcic et al. 1986et al. 1986AbuAbu--HejlehHejleh & & ZnidarcicZnidarcic, 1993, , 1993, WildenschildWildenschild et al. 1997, et al. 1997, AbdallahAbdallah 19991999

BicalhoBicalho 1999; Hwang 2002, 1999; Hwang 2002, ZnidarcicZnidarcic, Hwang & , Hwang & Bicalho Bicalho 20042004Testing technique with the flow control method (flow pump) Testing technique with the flow control method (flow pump) The selected flow rate determines how appropriate the stated assThe selected flow rate determines how appropriate the stated assumptions in the umptions in the

data interpretation. data interpretation.

ExperusExperus 2005:2005: LikosLikos, Lu & , Lu & WayllaceWayllace (numerical model)(numerical model)


Unsaturated air permeabilityUnsaturated air permeability

History: History:

•• Corey (1957)Corey (1957) (special permeability device (special permeability device –– siltysilty sand)sand)•• Yoshimi & Yoshimi & OsterbergOsterberg (1963)(1963)

(standard (standard oedometeroedometer connected to Uconnected to U--shape manometer)shape manometer)•• Delage, Cui & De Laure (1998)Delage, Cui & De Laure (1998) (k(kaa of a low plasticity compacted of a low plasticity compacted

silt) silt) •• LoiseauLoiseau, , Cui & Cui & DelageDelage (2002) (2002)

(k(kaa heavily compacted heavily compacted swelingsweling clayclay--sand mixture)sand mixture)

ExperusExperus 2005:2005:KamiyaKamiya,, BakrieBakrie & & HonjoHonjo:: Test method: Test method: kkaa –– SSrr relationship (sandy soils)relationship (sandy soils)Romero, Romero, GarcGarcííaa & & KnobelsdorfKnobelsdorf: Exp. study 80/20 sand/: Exp. study 80/20 sand/bentonitebentonite mixture mixture

Influence of the hydraulic history andInfluence of the hydraulic history and the the VVaa/V/Vss on on kkaa


CONCLUDING REMARKS CONCLUDING REMARKS Unsaturated water and air permeabilityUnsaturated water and air permeability

Reliable measurements and predictions of unsaturated Reliable measurements and predictions of unsaturated permeability functions are essential for solving any permeability functions are essential for solving any

unsaturated soil problemunsaturated soil problem

Direct measurements of unsaturated Direct measurements of unsaturated k functionsk functions should should always be preferred over the prediction using modelsalways be preferred over the prediction using models

Need of study comparing different Need of study comparing different methods (field?)methods (field?)


CONCLUDING REMARKS CONCLUDING REMARKS Unsaturated water and air permeabilityUnsaturated water and air permeability

Most of the existing methods yield the Most of the existing methods yield the kkww –– SSrr (or u(or uww) ) relationships, need of experimental study of relationships, need of experimental study of

kkww (soil structure + (soil structure + SSrr (or (or uuww))))

Highly nonlinear and challenging problemHighly nonlinear and challenging problem

Sophisticated experimental and analytical tools are needed to Sophisticated experimental and analytical tools are needed to address the problemaddress the problem

Today such tools are available, but a lot of fundamental work Today such tools are available, but a lot of fundamental work still needs to be still needs to be done (microscopic approach?)done (microscopic approach?)


Permeability in unsaturated swelling soilsPermeability in unsaturated swelling soilsIntroduction :Introduction :

Rigid soils:(1) Degree of Saturation - Suction curve (WRC)

(2) Unsaturated permeability - Suction curve k(s)

Swelling soils:(3) Shrinkage swelling curve (SSC)

Specific volume - Moisture content

Simultaneous measurement of three functions (Angulo 1989, Garnier et al. 1997)

Separate experiments (Kim et al. 1993)

Non linear Hysteresis


Permeability in unsaturated swelling soilsPermeability in unsaturated swelling soils

Constant Volume Oedometric

Three different boundary conditions:

Free Swelling



Dual gamma-ray bulk density ρd & volumetric water content θAngulo (1989), Tabani (1999), Rolland (2002), Rolland et al. (2005)

Tensiometers suctionAngulo (1989), Garnier et al. (1997)

Thermocouple psychrometer suctionBulut et al. (2005)Other separate methods

Laser spots, laser barriers swelling rateGarnier et al. (1997), Rolland (2002) Contact sensors swelling rateAngulo (1989), Kim et al. (1992)

Different testing methods (WRC) - (k(s) - (SSC) :



Free Swelling:

γ sources Detector

Soil

spec

imen

Strain gauge

Lasertransmitter

d = ± 3µm

Sensivities :ρd ± 0.04 g/cm3w = ± 3%

θw ± 0.04 cm3/cm3

Dual gamma-ray : Angulo (1989), Rolland (2002), Rolland et al. (2005)



Garnier et al. (1997)

Apparatus used to determine the hydraulic properties of a sample of swelling soil

under evaporation (t = 27 °C)

Eulerian method

Sensivities :

Laser spot : 2 µmLaser barriers : 100 µm

Tensiometers ± 2 cm H2O

Free Swelling:


Permeability in unsaturated swelling soilsPermeability in unsaturated swelling soilsConstant Volume :

Dual gamma-ray : Tabani (1999), Rolland (2002), Rolland et al. (2005)

ρd ± 0.04 g/cm3w = ± 3%

θw ± 0.04 cm3/cm3Sensivities :



Swelling an element in motion in a fluid system2 distinct approaches to unsteady problems may be used :

Eulerian Spatial coordinates independent variables (t)velocities and pressure heads dependent varibles (t)

Prager (1953), Philip (1968), Nakano et al. (1986), Kim et al. (1999)

Lagrangian Spatial (material) coordinates dependent varibles (t)

Hartley & Crank (1949), Gibson et al. (1967), Smiles & Rosenthal (1968),

Philip 1968, Angulo (1986), Nakano et al. (1986), Kim et al. (1999),

Tabani (1999), Rolland (2002)

Governing equations for water flow in swelling soils:



Nakano et al. (1986)(Japanese Bentonite : Bulk density

0.846 g/cm3)

Permeability (k) as a function of volumetric water content (θ)

Kim et al. (1999)(compacted mixture of 20% Bentonite

and loam)

θ



ρs(g/cm3)Soils

Xeuilley Silt

Bentonite

wp (%) IpwL (%)

2.67 233053

164 64 1002.7

ρs(g/cm3)Soils

Xeuilley Silt

Bentonite

wp (%) IpwL (%)

2.67 233053

164 64 1002.7

ρs(g/cm3)Soils

Xeuilley Silt

Bentonite

wp (%) IpwL (%)

2.67 233053

164 64 1002.7

40%

60%

Free Swelling test results (Rolland et al. Experus2005):

0

2

4

6

8

10

12

14

1.00 1.10 1.20 1.30 1.40 1.50 1.60

Hau

teur

(cm

)

ρd(g/cm3)

Bulk density before and after infiltration test. Gravimetric water content before and after infiltration test.

0

2

4

6

8

10

12

14

0 10 20 30 40 50 60H

aute

ur (

cm)

Initial and final profiles:

w(%)



HYDRIC TRANSFERLAGRANGIAN DESCRIPTION

(Philip, 1969)

m is the material coordinate

Boundary Conditions

with

∂∂

∂∂=

∂∂

mw)w(D

mtw

m dzdm s ⋅θ=

∞→=≥==

mfor)initial(ww0tand0mfor)saturation(ww

BOLTZMANN TRANSFORMATION

tm=ξ

ξ+

ξξ−=

ξ

2m

m2

2

ddw

dw)w(dD

ddw

21

)w(D1

dwd

Boundary Conditions

∞→ξ==ξ=

for)initial(ww0for)saturation(ww

Free Swelling test results (Rolland et al. Experus 2005):

Ordinary differential equation



Water content versus boltzmann variable.

Material diffusivity parameters identified by inverse method.

0

10

20

30

40

50

60

0.0 1.0 2.0 3.0

m/t1/2 (cm/d1/2)

w (

%) GARDNER’S MODEL :

)wbexp(aD mm)w(m =

GARDNER’S MODEL : )wbexp(aD mm)w(m =

0E+00

2E-10

4E-10

6E-10

8E-10

1E-09

20 25 30 35 40 45 50

w (%)

Dm

(m

2 /s)

Free swelling




0

5

10

15

20

25

0.2 0.3 0.4 0.5

θw

Suct

ion

(x 1

03 k

Pa)

Water retention curve (osmotic et filter paper methods)




θ

θ∂ψ∂

θθ

θθ

−=

2s

ww

ws

sw

m

s/wdd1D

K

Hydraulic conductivity

Effect of the mechanical boundary conditions


1E-15

1E-14

1E-13

1E-12

1E-11

1E-10

1E-09

20 25 30 35 40 45 50

w (%)K

w/s

(m

/s)

Essai libre Essai oedométriqueTabani (1999)(perméamètre) Essai volume constant

Free swelling


CONCLUDING REMARKS CONCLUDING REMARKS Permeability in unsaturated swelling soilsPermeability in unsaturated swelling soils

Dynamics of moisture movement is extremely Dynamics of moisture movement is extremely complex in unsaturated swellingcomplex in unsaturated swelling--shrinking soils.shrinking soils.

Given the complexity of theoretical and Given the complexity of theoretical and analytical methods, rigorous nonanalytical methods, rigorous non--linear linear hysteretic analyses may not allways be justified.hysteretic analyses may not allways be justified.

The simplified methods in this domain should The simplified methods in this domain should be developed.be developed.


Special thanks to Alessandro

Thank you for your kind attention

Molte Grazie

State-of-the-art on HYDRAULIC TESTING IN UNSATURATED SOIL · 2005. 7. 8. · Bicalho 1999; Hwang...

Documents

Transcript of State-of-the-art on HYDRAULIC TESTING IN UNSATURATED SOIL · 2005. 7. 8. · Bicalho 1999; Hwang...