7 unsaturated soil and slope stability analysis_2

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UNSATURATED SOIL AND

SLOPE STABILITY ANALYSIS

PT. VALE Indonesia Geotechnical Course, Oct

2011

Paulus P. RahardjoRinda Karlinasari

RESIDUAL SOIL :

2

CIPULARANG TOLL ROADCIPULARANG TOLL PROJECT CONSTRUCTION

PLTA BESAI LAMPUNG CIPADA SLOPE

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3

?

Outline

1. Soil Formations

2. Phase Relationship

3. Physical Properties

4. Soil Classification

5. Shear Strength

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1. SOIL FORMATIONS

PT. INCO Geotechnical Course, April 2008

1.1 Rock Cycles

Soils

(Das, 1998)

The final products

due to weathering are

soils

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1.2 Weathering

Physical and chemical changes that occur in

sediments and rocks when they are exposed to

the atmosphere and biosphere

Not the same as erosion

Many factors can affect the weathering process

such as climate, topography, features of parent

rocks, biological reactions, and others.

Climate determines the amount of water and

the temperature.

1.2 Weathering

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TROPICAL ZONE

TROPICAL RESIDUAL SOIL :

WEATHERING PROCESS 10

Weathering Process at rocks

Weathering Profile

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1.2 Weathering

Mechanical Weathering

• Making little pieces out of big ones.

• Composition of original rocks does not change.

• Result: lithic fragments

Chemical Weathering

• Original minerals chemically break down.

• Result: formation of new minerals stable at Earth-surface conditions.

The principal agent of chemical weathering is water.

This process occurs because minerals formed deep in Earth’s interior are not

stable under the conditions on the surface of Earth.

Stability is generally the reverse of Bowen’s reaction series.

1.2 Weathering

More stable

Higher weathering resistance

(Das, 1998)Bowen’s reaction series

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1.2.Weathering

Residual soils- to remain at the original place

Transported soils-to be moved and deposited to other places

Residual soils :

In Indonesia area , the top layer of rock is decomposed into residualsoils due to the hot tropic climate and abundant rainfall .

Engineering properties of residual soils are different with those oftransported soils

The knowledge of "classical" geotechnical engineering is mostly basedon behavior of transported soils. The understanding of residual soils isinsufficient in general.

RESIDUAL SOIL

PROFILE :

Typical Residual Soil Profile (after Little,1969)(Wesley, 1988)

Distinction in residual zone, Blight (Tan, Y.C., dan Chow, C.M.,2003)

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1.3 Residual Soil

Saprolite: rock fabric is retained.

Residual soil: rock fabric is completely

destroyed.

The red or yellow color is due to the

presence of iron oxides.

(Guide, 1988)

V

II

I

III

IV

VIResidual

soils

Completely

decomposed

Highly

decomposed

Moderately

decomposed

Slightly

decomposed

Fresh

LATERITATION

Solubility versus pH for Common Ions

Acid

Base

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LATERITATION

pH=10 Al2O3 Fe(OH)3

(sesquioxides)SiO2

pH=2 Al2O3

CaCo3

(silica and bases)

ZONE OF

OSCILLATING

WATER LEVELS

HIGH - LOW

GROUND

WATER TABLE

C

PARTLY CONDUCIVE TO

LATERITE FORMATION

B

MOST CONDUCIVE TO

LATERITE FORMATION

A

NOT CONDUCIVE

TO LATERITE

FORMATION

18

0 200 400 600 800 100012001400160018002000

Feldspar: Na0.8Ca0.2Al1.2Si2.8O8

Quartz :SiO2

Chlorite : NaCl

Carbonate : CaCo3

Kaolinite: Al2Si2(OH)4

Halloysite:Al2Si2(OH)4+H2O

Illite: KH3O(AlMgFe)2(SiAl)4O10(OH)2)


Quartz :SiO2

Chlorite : NaCl

Carbonate : CaCo3




Chlorite : NaCl




Chlorite : NaCl




Goethite,Hematite: FeO(OH),Fe2O3

Chlorite : NaCl







8.5

-9.0

7.0

-7.5

5.5

-64

.0-4

.52

.0-2

.50

.5-1

.0

Peak Intensity (counts)

BH02 Cij

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19

BH02 Cij

0.5-1.0 m

BH02 Cij

2.0-2.5 m

BH02 Cij

4.0-4.5 m

20

BH02 Cij

7.0-7.5 m

BH02 Cij

8.5-9.0 m

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0 200 400 600 800 1000


Quartz :SiO2

Chlorite : NaCl

Carbonate : CaCo3


Quartz :SiO2

Chlorite : NaCl

Carbonate : CaCo3

Chlorite : NaCl

Chlorite : NaCl


Chlorite : NaCl



8.5

-9.0

7.0

-7.5

5.5

-6

4.0

-4.5

2.0

-2.5

0.5

-1

.0


BH02 Cij

Weathering Zone :

ZONE CLASSIFICATION IN UNSATURATED SOIL PROFILE

DRY SOIL

Discontinue water phase, Air was filled almost all the soil pore

S → 0%

2 PHASE ZONE

Continue water and air phase,

CAPILLARITY ZONE

Water was filled almost all the soil pore, Discontinue air phase

S → 100%

Water table

Water was filled all the soil pores, Air is dissolve in water

UN

SATU

RATED

SO

IL

(negative

pore

wate

r

pre

ssure

)

SATU

RATED

SO

IL

(posi

tif pore

wate

r pre

ssure

)

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VADOSE ZONE

VADOSE ZONE AND ENVIRONMENT INFLUENCE

Active Zone

ACTIVE ZONE

Active Zone (Nelson and Miller,1991)

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What is Negative Water Pressure/Suction ?

Water tends to flow from wet to dry part

of soil.

Dry part of soil have a potential to

attrack water, we called it “moisture

tension”.

In a vadose zone water flow through

capillary of soil to reach the dry part soil

or the more negatif moisture tension part.

In intent to do so, it have to overcome the

gravity forces.

25

Moisture Potential in a Plant

Transpiration

(Evaporation through

plants) at leaf made

it have the highest

moisture potential

The water moves from

a less negative soil

moisture tension to a

more negative tension

in the atmosphere.

26

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Microscophic Looks

Surface tension higher when

only small value of water

attached to a solid

27

Surface Tension 28

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MATRIX SUCTION MEASUREMENT

( Likos, dan Ning Lu, 2003)

2. PHASE RELATIONS


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2.1 Three Phases in Soils

S : Solid

W: Liquid

A: Air

2.2 Three Volumetric Ratios

(1) Void ratio e (given in decimal, 0.65)

(2) Porosity n (given in percent 100%, 65%)

(3) Degree of Saturation S (given in percent 100%, 65%)

)(

)(

s

v

VsolidsofVolume

VvoidsofVolumee

)(

)(

t

v

VsamplesoilofvolumeTotal

VvoidsofVolumen

%100)(

)(

v

w

VvoidsofvolumeTotal

VwatercontainsvoidsofvolumeTotalS

e1

e

)e1(V

eVn

s

s

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2.2.1 Engineering Applications (e)

Typical values Engineering applications:

Volume change tendency

Strength

(Lambe and Whitman, 1979)

Simple cubic (SC), e = 0.91, Contract

Cubic-tetrahedral (CT), e = 0.65, Dilate

2.2.1 Engineering Implications (e)(Cont.)

Hydraulic conductivity

Which packing (SC orCT) has higherhydraulic conductivity?

SC

e = 0.91

CT

e = 0.65

The fluid (water) can flow more easily through the

soil with higher hydraulic conductivity

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2.2.1 Engineering Applications (e)(Cont.)

SC

e = 0.91

CT

e = 0.65The finer particle cannot pass

through the void

Clogging

Filter

2.2.2 Engineering Applications (S)

Completely dry soil S = 0 %

Completely saturated soil S = 100%

Unsaturated soil (partially saturated soil) 0% < S < 100%

%100)(

)(

v

w

VvoidsofvolumeTotal


Volumetric water content :

%100)(

)(

t

w


VwatercontainsvoidsofvolumeTotal

Remember :

)(

)(

t

v


VvoidsofVolumen

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Residual water content (r) :

Magnitude of volumetric water content when increases in suction no longer has influence in degree of saturation

2.2.2 Engineering Applications (S) (cont)

Saturated phase Unsaturated phase

1. Volumetric Water Content

S = degree of saturation

e = void ratio

2. Degree of Saturation, S

n = porosity

e

eS

1

.

nS

2.2.2 Engineering Applications (S) (cont)

In saturated soil , S= 100 %, = n

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2.3 Density and Unit Weight

• Mass is a measure of a body'sinertia, or its "quantity ofmatter". Mass is not changed atdifferent places.

• Weight is force, the force ofgravity acting on a body. Thevalue is different at variousplaces (Newton's second law F= ma) (Giancoli, 1998)

• The unit weight is frequentlyused than the density is (e.g. incalculating the overburdenpressure).

w

s

w

s

w

ss

g

gG

mkNWater

mg

gravitytodueonacceleratig

Volume

gMass

Volume

WeightweightUnit

Volume

MassDensity

g

g

g

g

g

3

2

8.9,

sec8.9

:

,

,

2.4 Weight Relationships

Density of soila. Dry density

b. Total, Wet, or Moist density (0%<S<100%, Unsaturated)

c. Saturated density (S=100%, Va =0)

d. Submerged density (Buoyant density)

)(

)(

t

sd


MsolidssoilofMass

)(

)(

t

ws


MMsamplesoilofMass

)(

)(

t

wssat


MMwatersolidssoilofMass

wsat '

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2.5 Typical Values of Specific Gravity

(Lambe and Whitman, 1979)

(Goodman, 1989)

3. PHYSICAL PROPERTIES


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3.1 Grain Size Distribution

43

Coarse-grained soils:

Gravel Sand

Fine-grained soils:

Silt Clay

0.075 mm (USCS)

0.06 mm (BS)

Experiment

Sieve analysis Hydrometer analysis

(Head, 1992)

3.1 Grain Size Distribution (Cont.)

44

Log scale

(Holtz and Kovacs, 1981)

Effective size D10: 0.02 mm

D30: D60:

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3.1 Grain Size Distribution (Cont.)

• Describe the shape

Example: well graded

•Criteria

2)9)(02.0(

)6.0(

)D)(D(

)D(C

curvatureoftCoefficien

45002.0

9

D

DC

uniformityoftCoefficien

2

6010

2

30c

10

60u

mm9D

mm6.0D

)sizeeffective(mm02.0D

60

30

10

)sandsfor(

6Cand3C1

)gravelsfor(

4Cand3C1

soilgradedWell

uc

uc

46

• The presence of water in fine-grained soils can significantly affect

associated engineering behavior, so we need a reference index to clarify

the effects. (The reason will be discussed later in the topic of clay minerals)


In percentage

3.2. Atteberg Limit

PI

PLwLI n

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3.2 Atterberg Limits (cont.)

47

Liquid Limit, LL

Liquid State

Plastic Limit, PL

Plastic State

Shrinkage Limit, SL

Semisolid State

Solid State

Dry Soil

Fluid soil-water

mixture

Incr

ea

sing

wa

ter

conte

nt

3.2. Casagrande Method (ASTM D4318-95a)

48

N=25 blows

Closing distance =

12.7mm (0.5 in)


Device

The water content, in percentage, required to close a

distance of 0.5 in (12.7mm) along the bottom of the

groove after 25 blows is defined as the liquid limit

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3.3 Plastic Limit-PL49

The plastic limit PL is defined as the water content at which a soil thread with 3.2

mm diameter just crumbles.

ASTM D4318-95a, BS1377: Part 2:1990:5.3


3.4. Atteberg Limit vs Soil State

PI = LL-PL

(Wesley)

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3.5 Typical Values of Atterberg Limits 51

(Mitchell, 1993)

Iron Oxidation Zone 52

0.0

0.5

1.0

1.5

2.0

2.5

Natural Dry 60 deg C oven

dry

100 deg C oven

dry

(FeO + Al2O3) / SiO2BH 02 Cijengkol 0.5-1.0

Condition :

Natural Dry Al2O3/SiO2 0.742

FeO/SiO2 0.586

(FeO + Al2O3) / SiO2 1.327

FeO/Al2O3 0.796

60oC oven dry Al2O3/SiO2 0.721

FeO/SiO2 0.209

(FeO + Al2O3) / SiO2 1.615

FeO/Al2O3 0.279

100oC oven dry Al2O3/SiO2 0.769

FeO/SiO2 0.737

(FeO + Al2O3) / SiO2 2.108

FeO/Al2O3 0.880

Quartz, silica and iron oxide mass percentage at 4.0-4.5 m to 0.5-1.0 m at Cijengkol Slope

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Flocculasion and Dispersion53

0.5 – 1.0 m 4.0 – 4.5 m 7.0 – 7.5 m

PORE DIAMETER over DEPTH 54

0

10

20

30

40

50

60

70

80

0.001 0.01 0.1 1 10 100 1000 10000

Cum

mula

tive D

iam

ete

r (m

m)

Diameter (mm)

Diameter Pori per Kedalaman Lapisan

BH02 Cij 0.5-1.0 BH02 Cij 2.0-2.5 BH02 Cij 4.0-4.5 BH02 Cij 8.5-9.0

Aung et al, 2000

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RESEARCH PROGRAM : Physical Properties

BH 02 Neg Kedalaman

sampel

Ket BH

03

Neg

Kedalaman

sampel

Ket BH04

Neg

Kedalaman

sampel

Ket BH 05

Neg

Kedalaman

sampel

Ket

1 0.5-1.0 m SB 1 0.5-1.0 m SB 1 0.0-0.5 m SPT 1 0.5-1.0 m SB

2 1.5-1.95 m SPT 2 1.5-1.95 m SPT 2 0.5-1.0 m SB 2 1.5-1.95 m SPT

3 2.0-3.0 m SB 3 2.0-3.0 m SB 3 1.5-1.95 m SPT 3 2.5-3.0 m SB

4 3.5-3.95m SPT 4 3.5-3.95m SPT 4 2.5-3.0 m SB 4 3.5-3.95 m SPT

5 4.0-5.0 m SB 5 4.0-5.0 m SB 5 3.5-3.95 m SPT 5 4.5-5.5 m SB

6 5.5-5.95 m SPT 6 5.5-5.95 m SPT 6 4.5-5.0 m SB 6 5.5-5.95 m SPT

7 6.5-7.0 m SB 7 7.0-7.5 m SB 7 5.5-5.95 m SPT 7 6.5-7.0 m SB

8 7.5-7.95 m SPT 8 7.5-7.95 m SPT 8 6.5-7.0 m SB 8 8.5-9.0 m SB

9 8.5-9.0 m SB 9 8.5-9.0 m SB 9 7.5-7.95 m SPT 9 9.5-9.95 m SPT

10 9.5-9.95 m SPT 10 9.5-9.95 m SPT 10 8.5-9.0 m SB 10 10.5-11.50 m SB

11 11.5-11.95 m SPT 11 11.5-11.95 m SPT 11 9.5-9.75 m SPT 11 11.5-11.95 m SPT

12 13.0-13.5 m SB 12 13.5-13.95 m SPT 12 11.5-11.95 m SPT 12 13.5-13.95 m SPT




16 19.5-19.95 m SPT 16 25.5-25.95 m SPT 16 25.5-25.95 m SPT

17 21.5-21.95 m SPT 17 27.5-27.95 m SPT 17 27.5-27.95 m SPT

18 23.5-23.95 m SPT 18 29.5-29.95 m SPT 18 29.5-29.95 m SPT

19 25.5-25.95 m SPT

20 27.5-27.95 m SPT

55

Number of sampel

Physical Properties Profile56

Diagram of tropical residual soil profile (dari Little, 1969) Variation in engineering properties of weathering Basalt rock to Laterit Soil (Tuncer and Lohnes, 1977)

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Weathering Stage57

wVs

WsGs

g.

w

d

Vs

VGs

g

g

.

wVs

VwGsg

g

.

1.

wVs

VwGsg

g

.

1.

Vs

Vve

w

SeGs

.

Beginning of Oxidation Zone (Stage 4):

Stage 4, Sesquioxides (Fe2O3 dan Al2O3) increase, Specific Gravity increase . Increase on Specific Gravity, increase on density :

Increase on void ratio because increasing specific gravity means decrease on solid volume (Vs) :

Weathering Stage58

End of Oxidation Zone (Stage 5):

At stage 5 there is decrease on Degree of Saturation (S) , soil become more unsaturated. Unsaturated vol-mass relation apply :

At the last equation above, if density and specific gravity increase,then decrease on degree of saturation means decrease on void ratio.

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Unsaturated Vol-Mass Relationship

Void ratio e

Porosity n

Degree of Saturation S

)(

)(

s

v

VsolidsofVolume

VvoidsofVolumee

)(

)(

t

v


VvoidsofVolumen

%100)(

)(

v

w

VvoidsofvolumeTotal


e1

e

)e1(V

eVn

s

s

59

S : Solid W: Liquid A: Air

Unsaturated Vol-Mass Relationship60

w

SeGs

.

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61

0 200 400 600 800 100012001400160018002000


Quartz :SiO2

Chlorite : NaCl

Carbonate : CaCo3





Quartz :SiO2

Chlorite : NaCl

Carbonate : CaCo3




Chlorite : NaCl




Chlorite : NaCl





Chlorite : NaCl







8.5

-9.0

7.0

-7.5

5.5

-64

.0-4

.52

.0-2

.50

.5-1

.0


0

2

4

6

8

10

12

14

16

2.4 2.6 2.8

BH02 Cijengkol

Zone 4 - 5

Zone 3

BH02 Cij

PROPERTIES PROFILE BH02 Cijengkol

62

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SPECIFIC GRAVITY (Gs) 63

Typical Values of Specific Gravity

(Mitchel 1982)

(Goodman, 1989)

64

Mineral PrimerOrthoclase feldspars 2.5 – 2.6Serpentine 2.5 – 2.8Quartz 2.65Plagioclase feldspars 2.61-2.75Hornblende 2.9 – 3.3Augite 3.3 – 3.6Mineral SekunderKaolinite 2.2 – 2.6Gibbsite 2.4Goethite 3.3 – 3.5Hematite 4.9 – 5.3

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Void Ratio65

Liquid Limit66

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Typical Values of Atterberg Limits

67

(Mitchell, 1993)

CLAY CONTENT68

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PLASTICITY CHART69

0 40 80 120 160 200 240 Liquid Limit

80

40Pla

sticity I

nd

ex A-lin

e

60

20

100Weathered sedimentary soilsRed volcanic clays

Volcanic ash (allophane)

0

20

40

60

80

100

0 40 80 120 160 200 240

Pla

sti

city

Index

Liquid Limit

BH05 Neg

BH04 Neg

BH03 Neg

BH02 Neg

BH01 Cil

BH03 Cij

BH02 Cij

Diagram Cassagrande dan hasil pengujian Wesley untuk tanah-tanah residual (Wesley, 2004)

Diagram Cassagrande hasil pengujian pada penelitian ini

70

Rao, Sivapullaiah, Padmanabha (1988) memberikan korelasi empiris :

Thomas Paal dan Post (1984) memberikan korelasi empiris :

Nagaraj dan Jayadeva (1984) memberikan korelasi empiris :

This research : )75735.32(816.0 xIP

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71

YUDBHIR DAN SAHU CLASSIFICATION (1988)

0

20

40

60

80

100

0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00

Activity, Ac

BH02 Cij BH03 Cij BH01 Cil BH02 Neg

BH03 Neg BH04 Neg BH05 Neg

Pla

stic

ity

Ind

ex ,

PI

0

20

40

60

80

100

0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00

Activity, Ac

Zone 5 Zone 4 Zone 3

Pla

stic

ity

Ind

ex ,

PI

72

Results in activity and plasticity diagram Vargas (1985)

Vargas research results on many types of residual soil and this research results

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ACTIVITY CHART vs ZONE 73

0

20

40

60

80

100

020406080100

% clay (f < 2m)

Zone 5 Zone 4 Zone 3

Active

Normal

Inactive

Pla

stic

ity

Ind

ex

%

This research results : Different zone in the activity diagram

WESLEY CLASSIFICATION (1988)74

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75

This research results and the its distance from A-line

WESLEY CLASSIFICATION (1988)

76

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1

% f

iner

Diameter, mm

BH02 Cij 0.5-1.0

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1

% fin

er

Diameter, mm

BH02 Cij 1.0-1.5

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1

% f

iner

Diameter, mm

BH02 Cij 2.0-2.5

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1

% f

iner

Diameter, mm

BH02 Cij 2.5-3.0

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1

% f

iner

Diameter, mm

BH02 Cij 4.0-4.5

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.01 1

% f

iner

Diameter, mm

BH02 Cij 5.0-5.5

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.01 1

% f

iner

Diameter, mm

BH02 Cij 7.0-7.5

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1

% f

iner

Diameter, mm

BH02 Cij 8.5-9.0

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.01 1

% f

iner

Diameter, mm

BH02 Cij 9.5-10.0

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GRAIN-SIZE DISTRIBUTION 77

0

10

20

30

40

50

60

70

80

90

100

0.0001 0.001 0.01 0.1 1 10 100

% F

ine

r

Diameter, mm

BH02 0.5-1.0

BH02 1.5-2.0

BH02 2.0-2.5

BH02 2.5-3.0

BH02 4.0-4.5

BH02 5.0-5.5

BH02 7.0-7.5

BH02 8.5-9.0

BH02 9.5-10.0

BH02 14.5-15.0

4. SOIL CLASSIFICATION


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79

4.1. Purpose

Classifying soils into groups with similar behavior, in terms of

simple indices, can provide geotechnical engineers a general

guidance about engineering properties of the soils through the

accumulated experience.

Simple indices

Grain SD, LL, PI

Classification system

(Language)Estimate

engineering

properties

Achieve engineering

purposes

Use the

accumulated

experience

Communicate

between

engineers

80

4.2. Classification Systems

• Unified Soil Classification System (USCS).

• Residual Soil Classification

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4.3. Unified Soil Classification System

(USCS)81

Origin of USCS:

This system was first developed by Professor A. Casagrande

(1948) for the purpose of airfield construction during World

War II. Afterwards, it was modified by Professor Casagrande,

the U.S. Bureau of Reclamation, and the U.S. Army Corps of

Engineers to enable the system to be applicable to dams,

foundations, and other construction (Holtz and Kovacs, 1981).

Four major divisions:

(1) Coarse-grained

(2) Fine-grained

(3) Organic soils

(4) Peat

82

4.3.1 Definition of Grain Size

Boulders Cobbles

Gravel Sand Silt and

Clay

Coarse Fine Coarse FineMedium

300 mm 75 mm

19 mm

No.4

4.75 mm

No.10

2.0 mm

No.40

0.425 mm

No.200

0.075

mm

No specific grain

size-use

Atterberg limits

10/22/2011

42

83

4.3.2 Plasticity Chart


LL

PI

HL• The A-line generally

separates the more

claylike materials

from silty materials,

and the organics

from the inorganics.

• The U-line indicates

the upper bound for

general soils.

Note: If the measured

limits of soils are on

the left of U-line,

they should be

rechecked.

84

4.3.3 Procedures for Classification

Coarse-grained

material

Grain size

distribution

Fine-grained

material

LL, PI

(Santamarina et al.,

2001)

Highly

10/22/2011

43

4.4. Residual soil : Pedology Classification

French Classification FAO Soil TaxonomyJuvenile soil on recent alluvium andcolluvium

FLUVISOLS Fluvent

Juvenile soils on recent eolian depositsand weakly developed soils

REGOSOLS PsammentsOrthents

Ferralitic soils on loose sandysediments

ARENOSOLS Ferralic A Oxic Quatzipsamments

Mineral hydromorphic soils GREYSOLSEutric GDystric GHumic G

Tropaquepts

Hydromorphic soils with anaccumulation of iron or a plinthitehorizon

Plintic G Plinthaquepts

Eutropic brown soils of tropicalregions on volcanic ash

ANDOSOLS Andepts

PLANOSOLSCAMBISOLS

Ferralitic soils, rejuvenited; Dystric C DystropeptsFerruginous or ferralitic soils,rejuvenated;

Eutric C Eutropepts

Ferralitic soils, humic,rejuvenated Humic C Humitropepts3. Ferruginous tropical soils LUVISOLS Tropudalfs

PaleudalfsPaleustalfs

Yellowish-brown Ferralitic Soils ACRISOLSRhodic A. Rhodudults

RhodustultsFerralitic soils FERRALSOLS OxisolsLithosols and lithic soils LITHOSOLS Lithic subgroupsFerrisols NITOSOLS

(some cambisols)Udalfs (?)

Vertisols VERTISOL Vertisols

Modificated by Morin and Todor, 1975 ; Mitchell, 1982

4.4. Residual soil : Composition Classification

MAJOR DIVISION SUB-GROUP EXAMPLES COMMENTS

GROUP ASoil without a strong mineralogical influence

(a) Strong macro-structureinfluence

Moderately weathered to highlyweathered soils (from Granite,sandstone, etc)

Nature of macro-structure needsdefinition- stratification- fracture, fissures, voids, etc

(b) Strong micro-structureinfluence

Completely weathered soils (i.e. trueresidual soils from granite, sandstone, etc

Remoulding likely to stronglyinfluence behaviour-sensitivy should be a usefulindicator

(c) Little or no structure influence Probably a rather minor sub-group

GROUP BSoils stronglyinfluenced by‘normal’ clay mineral

(a) Smectite (montmorillinite) group

Black cotton soils (Black clay,vertisols, tropical black earth,grumusols)

Problems soils, characterisised by low strength, high compressibility, high shrink swell behaviour (similar characteristics to any montmorillinite soil)

(b) other minerals ? ??

GROUP CSoils stronglyinfluenced by clayminerals found onlyin residual soils

(a) Allophane Volcanic Ash Soils (andosols,Andepts)

Low activity soils, with good engineering properties, characterized by very high water contents and large irreversible changes on drying

(b) Halloysite Red clays of volcanic origin (latosols,oxixols, ferrasols)

Low activity soils, good engineeringproperties

(c) Sesquioxide Gibbsite,Geothite Lateritic soilsLaterites

Extremely variable group, rangingfrom silty clay to gravel

(Wesley)

10/22/2011

44

5. SHEAR STRENGTH


SHEAR STRENGTH

Unsaturated Soil Shear Strength

Saturated Soil Shear Strength

10/22/2011

45

STRESS STATE ON A CUBICLE SOIL ELEMENT

azyzxz

zyayxy

zxyxax

u

u

u

wa

wa

wa

uu

uu

uu

00

00

00

Stress State Variable for Unsaturated Soil (Fredlund, D.G., and Vanapalli, S.K. )

Balanced condition on soil

structure :

and air-water inter phase

(contractile skin) :

Suction

Suction is a negative pore water pressure, formulated as :

wa uus ua = pore air pressure

uw = pore water pressure

ua = 100 kPa

uw = 0 kPa

water table

s = 100 kPa

ua= uw

s = 0

10/22/2011

46

FAILURE CRITERION

A consistent relationship exists between the

shear strength on a plane and the effective

normal stress that acts on that plane

S = c’ + ’ tan f’ where

S = shear strength on the plane

’= effective normal stress on the plane

c’ = effective cohesion

f’ = effective friction angle

FAILURE ENVELOPE

Mohr-Coulomb failure envelope

10/22/2011

47

FAILURE ENVELOPE of UNSATURATED SOIL

b

fwa

'

faf

'

ff uuuc ff tantan

(Fredlund & Rahardjo, 1993)

Non-Linear fb

NON-LINEAR FAILURE ENVELOPE UNSATURATED SOIL

10/22/2011

48

DETERMINATION OF SHEAR STRENGTH

FROM TEST RESULTS (DS, TX)

Selection of failure criteria depends on:

1. Testing condition

2. Field condition (Drained vs. Undrained)

DRAINED STRENGTH

Shear strength defined in terms of effective normal

stresses is referred as “drained” or “effective” strength

To use drained or effective strength, effective normal

stresses need to be known which, in turn, requires that

pore water pressures are known

Pore pressures may not be simple to determine in the

Field

Typically used in analysis of stability of excavation slopes

and natural slopes.

10/22/2011

49

UNDRAINED STRENGTH

In those cases, such as at end of construction in

fine-grained soils, where determination of pore

pressures are difficult “undrained” or “total”

strength is used for convenience

S = cu + tan fu where cu = undrained cohesion

and fu = undrained friction angle (zero for

saturated soils), and = total normal stress

Typically used in foundation, retaining wall,

embankment slope design.

98

DETERMINATION OF SHEAR STRENGTH FROM UNSATURATED

TEST RESULTS (DS, TX UNSAT)

MODIFIED DIRECT SHEAR APPARATUS

10/22/2011

50

99



AXIS TRANSLATION TECHNIQUE

100



MODIFIED

DIRECT SHEAR APPARATUS

FOR

WATER INFILTRATION

TEST

10/22/2011

51

101



MODIFIED DS APPARATUS

FOR WATER INFILTRATION TEST

102



MODIFIED TRIAXIAL

TESTING APPARATUS

10/22/2011

52

Method 1: Free pressure condition (Fredlund et al., 1978)

c’ = effective cohesion

(f – ua)f = normal pressure variable at failure plane on failure

(ua – uw)f = suction at failure plane on failure

f ’ = internal friction angle, defined the increased in shear strength due to

increased on normal total pressure

f b = defined the increased in shear strength due to suction

b

fwa

'

faf

'

ff uuuc ff tantan

UNSATURATED SOIL STRENGTH FAILURE CRITERION

’ (effective pressure)

c = effective pressure parameter

Method 2: Effective pressure (Bishop, 1959)

'tan' fc waan uuuc


10/22/2011

53

(ua – uw)b: air entry value (AEV)

c : a function from soil’s matric suction

(Khalili & Khabbaz, 1988)

Sr: Residual degree of saturationS : Degree of saturation on Critical condition

c : a function from degree of saturation (S)

(Tohari, 2002)

55.0

bwa

wa

uu

uuc

r

r

S

SS

100c


(v – ua) = vertical total normal pressure

ua = pore air pressure

(z) = soil density, function of depth

z1 = soil surface elevation

z2 = certain point elevation

g = gravitation acceleration

In geostatic condition (flat surface, no vertical and horizontal shear pressure) :

a

z

zav udzgzu

1

2

z1

z2

horizontal soil surface

(v – ua) = g (z1-z2)

INSITU PROFILE FOR UNSATURATED SOIL

10/22/2011

54

For unsaturated soil :

(v – ua) = vertical total normal pressure

av

ah

u

uK

z1

z2

Horizontal soil surface

(h – ua) = K0 (v – ua)

(v – ua)

(h – ua)

(h – ua) = horizontal total normal pressure

LATERAL SOIL PRESSURE COEFFICENT

where,

m = Poisson’ ratioE = Elastic Modulus due to change on vertical total pressure

(v – ua)H = Elastic Modulus due to change on suction

av

wa

u

uu

H

mEK

m

m 1

10

Elastic Equilibrium :

UNSATURATED SOIL COEFFICIENT OF HORIZONTAL PRESSURE AT REST

10/22/2011

55

Matrix Suction Measurement 109

Main part of Jetfill Tensiometer (Soil Moisture)

110

Rain Session Monitoring

12/27/05 12:0012/27/05 13:0012/27/05 14:0012/27/05 15:0012/27/05 16:0012/27/05 17:0012/27/05 18:0012/27/05 19:0012/27/05 20:0012/27/05 21:0012/27/05 22:0012/27/05 23:0012/28/05 0:0012/28/05 1:0012/28/05 2:0012/28/05 3:0012/28/05 4:0012/28/05 5:0012/28/05 6:0012/28/05 7:0012/28/05 8:0012/28/05 9:00

12/28/05 10:0012/28/05 11:0012/28/05 12:0012/28/05 13:0012/28/05 14:0012/28/05 15:0012/28/05 16:0012/28/05 17:0012/28/05 18:0012/28/05 19:0012/28/05 20:0012/28/05 21:0012/28/05 22:0012/28/05 23:0012/29/05 0:0012/29/05 1:0012/29/05 2:0012/29/05 3:0012/29/05 4:0012/29/05 5:0012/29/05 6:0012/29/05 7:0012/29/05 8:0012/29/05 9:00

12/29/05 10:0012/29/05 11:0012/29/05 12:0012/29/05 13:0012/29/05 14:0012/29/05 15:0012/29/05 16:0012/29/05 17:0012/29/05 18:00

0 1 2 3 4 5 6 7 8 9 10111213141516171819202122232425

Tanggal dan J

am

pem

baca

an

Matriks Suction (kPa)

Siklus Matriks Suction pada 27 to 29 Des 2005

BJF 1 depth 0.6 m BJF 2 depth 1.2 m

BJF 3 depth 2.1 m

10/22/2011

56

111

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0123456789

10111213141516171819202122232425

12

/2

7/05

12

:00

12

/2

7/05

13

:00

12

/2

7/05

14

:00

12

/2

7/05

15

:00

12

/2

7/05

16

:00

12

/2

7/05

17

:00

12

/2

7/05

18

:00

12

/2

7/05

19

:00

12

/2

7/05

20

:00

12

/2

7/05

21

:00

12

/2

7/05

22

:00

12

/2

7/05

23

:00

12

/2

8/05

0:0

01

2/2

8/05

1:0

01

2/2

8/05

2:0

01

2/2

8/05

3:0

01

2/2

8/05

4:0

01

2/2

8/05

5:0

01

2/2

8/05

6:0

01

2/2

8/05

7:0

01

2/2

8/05

8:0

01

2/2

8/05

9:0

01

2/2

8/05

10

:00

12

/2

8/05

11

:00

12

/2

8/05

12

:00

12

/2

8/05

13

:00

12

/2

8/05

14

:00

12

/2

8/05

15

:00

12

/2

8/05

16

:00

12

/2

8/05

17

:00

12

/2

8/05

18

:00

12

/2

8/05

19

:00

12

/2

8/05

20

:00

12

/2

8/05

21

:00

12

/2

8/05

22

:00

12

/2

8/05

23

:00

12

/2

9/05

0:0

01

2/2

9/05

1:0

01

2/2

9/05

2:0

01

2/2

9/05

3:0

01

2/2

9/05

4:0

01

2/2

9/05

5:0

01

2/2

9/05

6:0

01

2/2

9/05

7:0

01

2/2

9/05

8:0

01

2/2

9/05

9:0

01

2/2

9/05

10

:00

12

/2

9/05

11

:00

12

/2

9/05

12

:00

12

/2

9/05

13

:00

12

/2

9/05

14

:00

12

/2

9/05

15

:00

12

/2

9/05

16

:00

12

/2

9/05

17

:00

12

/2

9/05

18

:00

Rain

fall Inte

nsi

ty (

mm

/hr)

Matr

ix S

uct

ion (

kPa)

Tanggal dan jam pembacaan

Siklus Matriks Suction pada 27 to 29 Des 2005

BJF 1 depth 0.6 m BJF 2 depth 1.2 m BJF 3 depth 2.1 m Hujan

112

8/11/06 12:00

8/11/06 13:00

8/11/06 14:00

8/11/06 15:00

8/11/06 16:00

8/11/06 17:00

8/11/06 18:00

8/11/06 19:00

8/11/06 20:00

8/11/06 21:00

8/11/06 22:00

8/11/06 23:00

8/12/06 0:00

8/12/06 1:00

8/12/06 2:00

8/12/06 3:00

8/12/06 4:00

8/12/06 5:00

8/12/06 6:00

8/12/06 7:00

8/12/06 8:00

8/12/06 9:00

8/12/06 10:00

8/12/06 11:00

8/12/06 12:00

8/12/06 13:00

8/12/06 14:00

8/12/06 15:00

8/12/06 16:00

15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Tanggal dan J

am

Pem

baca

n


Siklus Matriks Suction pada11 sampai 12 Agustus 2006


Dry Session Monitoring

10/22/2011

57

RAINFALL DATA113

0

10

20

30

40

50

60

4/26/05

0:00

5/26/05

0:00

6/25/05

0:00

7/25/05

0:00

8/24/05

0:00

9/23/05

0:00

10/23/05

0:00

11/22/05

0:00

12/22/05

0:00

1/21/06

0:00

2/20/06

0:00

3/22/06

0:00

4/21/06

0:00

Date

Rain

fall I

nte

nsit

y (

mm

/h

)

0

200

400

600

800

1000

1200

1400

1600

1800

2000

Tota

l R

ain

fall (

mm

)

I (mm/hr)

Total (mm)Rainfall Data Lereng Cijengkol

Tahun 2005 - 2006

114

15-December-2005

14-January-2006

13-February-2006

15-March-2006

14-April-2006

14-May-2006

13-June-2006

13-July-2006

12-August-2006

11-September-2006

1011121314151617181920212223242526272829

Tanggal pem

baca

an


Profil Matriks Suction dari Desember 2005 - Agustus 2006


15-December-2005

15-January-2006

14-February-2006

17-March-2006

16-April-2006

17-May-2006

16-June-2006

17-July-2006

5 6 7 8 9 10 11 12 13 14 15

Tanggal Pem

baca

an


Profil Matriks Suction BJF 1 diantara

jam 10.00-15.00 dari Desember 2005 sampai Juli 2006

BJF 1 depth 0.6 m

10/22/2011

58

115

Volumetric Water Content Measurement

¾’ BSP Thread

40 mm dia

3 mm dia rods, 4 off

60 mm

112 mm

36 mm

116

Vol. Water Content

Monitoring Result

15-December-2005

14-January-2006

13-February-2006

15-March-2006

14-April-2006

14-May-2006

13-June-2006

13-July-2006

12-August-2006

40.00 45.00 50.00 55.00 60.00 65.00

Tanggal

Pem

baca

an

Volumetric Water Content (%)

Profil Vol Water Content dari Desember 2005 - Agustus 2006

THETAPROBE 1 (0.6 m) THETAPROBE 2 (1.2 m)

12/27/05 12:00

12/27/05 14:00

12/27/05 16:00

12/27/05 18:00

12/27/05 20:00

12/27/05 22:00

12/28/05 0:00

12/28/05 2:00

12/28/05 4:00

12/28/05 6:00

12/28/05 8:00

12/28/05 10:00

12/28/05 12:00

12/28/05 14:00

12/28/05 16:00

12/28/05 18:00

12/28/05 20:00

12/28/05 22:00

12/29/05 0:00

12/29/05 2:00

12/29/05 4:00

12/29/05 6:00

12/29/05 8:00

12/29/05 10:00

12/29/05 12:00

12/29/05 14:00

55 55.5 56 56.5 57 57.5 58

Tanggal dan J

am

pem

baca

an

Vol Water Content (%)

Profil Vol. Water Content pada

27 to 29 Des 2005

8/11/06 12:00

8/11/06 13:00

8/11/06 14:00

8/11/06 15:00

8/11/06 16:00

8/11/06 17:00

8/11/06 18:00

8/11/06 19:00

8/11/06 20:00

8/11/06 21:00

8/11/06 22:00

8/11/06 23:00

8/12/06 0:00

8/12/06 1:00

8/12/06 2:00

8/12/06 3:00

8/12/06 4:00

8/12/06 5:00

8/12/06 6:00

8/12/06 7:00

8/12/06 8:00

8/12/06 9:00

8/12/06 10:00

8/12/06 11:00

8/12/06 12:00

8/12/06 13:00

8/12/06 14:00

8/12/06 15:00

8/12/06 16:00

4040.54141.54242.543

Vol Water Content (%)

Profil Vol. Water Content

11 to 12 Agustus 2006

THETAPROBE 1 (0.6 m)

10/22/2011

59

117

Suction Measurement : Filter Paper Method

118

0%

20%

40%

60%

80%

1 10 100 1000 10000100000

Wate

r co

nte

nt

(%)

Suction (kPa)

BH02 Neg 0.5-1.0 m

0%

20%

40%

60%

80%

1 10 100 1000 10000100000

Wate

r co

nte

nt

(%)

Suction (kPa)

BH02 Neg 6.5-7.0 m

0%

20%

40%

60%

80%

1 10 100 1000 10000100000

Wate

r co

nte

nt

(%)

Suction (kPa)

BH02 Neg 2.5-3.0 m

Suction Measurement Result : Filter Paper Method

10/22/2011

60

119

Matrix Suction Profile

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

1 100 10000

Depth

(m

)Suction (kPa)

Matriks Suction

& Total Suction BH02 Cij (w = 40 %)

Zone 5

Zone 4

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

1 100 10000

Depth

(m

)

Suction (kPa)

Matriks Suction

& Total Suction BH02 Neg (w = 40 %)

Matriks Suction Total Suction

Zone 5

Zone 4

Zone 3

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

1 100 10000

Depth

(m

)

Suction (kPa)

Matriks Suction


Matriks Suction Total Suction

Zone 3

Zone 40.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

1 100 10000

Depth

(m

)

Suction (kPa)

Matriks Suction


Matriks Suction

Colluvial

Zone 5

Zone 4

Zone 3

wa uu

120

RESEARCH PROGRAM : Shear Strength Characteristics

10/22/2011

61

121

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0 1 2 3 4 5 6

Str

ess (

kg

/cm

2)

Axial Strain (%)

Stress-Strain curveTX CU

0.2 kg/cm20.6 kg/cm21.4 kg/cm2

BH02 Cij 2.0-2.5 m

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5S

hear

Str

en

gth

(kg

/cm

2)

Tegangan Normal (kg/cm2)

Mohr Circle ESP 0.2 kg/cm2

ESP 0.6 kg/cm2

ESP 1.4 kg/cm2

TSP 0.2 kg/cm2

TSP 0.6 kg/cm2

TSP 1.4 kg/cm2

Total

Efektif

BH02 Cij 2.0-2.5 m

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0 1 2 3 4 5 6

Po

re W

ate

r P

ressu

re(kg

/cm

2)

Axial Strain (%)

Pore Water

Pressure - Strain

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5

q (

kg

/cm

2)

p , p' (kg/cm2)

p - q Diagram

TSP 0.2 kg/cm2

ESP 0.2 kg/cm2

TSP 0.6 kg/cm2

ESP 0.6 kg/cm2

TSP 1.4 kg/cm2

ESP 1.4 kg/cm2

total

efektif

TX CU BH02 Cij 2.0-2.5 m

122

No. Lokasi Sampel c f c' f'

1 TX CU Cijengkol BH02 0.50-1.00 0.21 19.0 0.23 22.0








9 TX CU Cilame BH01 0.50-1.00 0.26 22.5 0.29 25.0

10 TX CU Cilame BH01 2.50-3.00 0.26 18.0 0.18 27.0

11 TX CU Cilame BH01 4.50-5.00 0.37 27.0 0.41 32.0

12 TX CU Neglajaya BH02 0.50-1.00 0.15 20.0 0.19 26.5




















10/22/2011

62

123

This Research : c f c' f'

Maximum 0.66 32.50 0.69 37.00

Median 0.26 24.00 0.28 28.00

Minimum 0.06 16.00 0.09 22.00

Average 0.29 23.79 0.31 29.29

Mode 0.26 24.00 0.30 27.00

Standard Deviasi 0.14 4.19 0.15 4.09

SHEAR STRENGTH

Unsaturated Soil Shear Strength

Saturated Soil Shear Strength

124

10/22/2011

63

Unsaturated Triaxial Consolidated Drained Test

125

TXCD-UNSAT APPARATUS (NTU- SING)

126

NTU GEO LAB

10/22/2011

64

TXCD-UNSAT Diagram (NTU-Sing)

127

TXCD-UNSAT Diagram (UNPAR)128

10/22/2011

65

TRIAXIAL CELL PEDESTAL (TXCD-UNSAT)

129

TEST STAGES 130

STAGE 1 ua uw -ua ua-uw

Consolidation 1.8 0.8 1

Matrix suction equalisation 1.8 0.8 0.4 1 0.4

Shearing 1.8 0.8 0.4 1 0.4

STAGE 2

Consolidation 2.6 1.2 1.4

Matrix suction equalisation 2.6 1.2 0.4 1.4 0.8

Shearing 2.6 1.2 0.4 1.4 0.8

STAGE 3

Consolidation 3 1.4 1.6

Matrix suction equalisation 3 1.4 0.4 1.6 1

Shearing 3 1.4 0.4 1.6 1

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66

MATRIX SUCTION EQUALISATION STAGE (TXCD-UNSAT)

131

-25.0

-20.0

-15.0

-10.0

-5.0

0.0

0 5 10 15 20 25

Wate

r vo

lum

e c

hang

e,

DV

w (c

m3)

Elapsed time, t (hours)

ua-uw = 0.29 kg/cm2

ua-uw = 0.68 kg/cm2

ua-uw = 0.89 kg/cm2

BH02 Cijengkol 0.5-1.0 m

ua-uw = 0.29 kg/cm2

ua-uw = 0.68 kg/cm2

ua-uw = 0.89 kg/cm2


-9.0

-8.0

-7.0

-6.0

-5.0

-4.0

-3.0

-2.0

-1.0

0.0

0 5 10 15 20 25

To

tal

vo

lum

e c

hang

e,

DV

t (c

m3)

Elapsed time, t (hours)

ua-uw = 0.29 kg/cm2

ua-uw = 0.68 kg/cm2

ua-uw = 0.89 kg/cm2


132

0.0

0.5

1.0

1.5

2.0

2.5

3.0

0.00 2.00 4.00 6.00

Devia

tor S

tress (

kg/cm

2)

Axial Strain (%)

Stress-Strain curve

TXCD Unsat BH02 Cij 0.5-1.0 m

ua-uw = 0.29 kg/cm2ua-uw = 0.68 kg/cm2ua-uw = 0.89 kg/cm2

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0.00 2.00 4.00 6.00 8.00

Devia

tor

Str

ess (

kg/cm

2)

Axial Strain (%)

Stress-Strain curve

TXCD-Unsat BH01 Cil 4.5-5.0 m

ua-uw = 0.4 kg/cm2

ua-uw = 0.8 kg/cm2

ua-uw = 1 kg/cm2

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0.00 2.00 4.00 6.00

Devia

tor

Str

ess (

kg/cm

2)

Axial Strain (%)

Stress-Strain curve

TXCD-Unsat BH03 2.5-3.0 m

ua-uw = 0.07 kg/cm2

ua-uw = 0.26 kg/cm2

ua-uw = 0.35 kg/cm2

10/22/2011

67

TX-CD UNSAT RESULT ANALYSIS 133

azyzxz

zyayxy

zxyxax

u

u

u

Tegangan normal dan geser pada suatu elemen tanah tak jenuh (a) mengikuti pendekatan independen stress variable (b) mengikuti pendekatan efektif stress

wa

wa

wa

uu00

0uu0

00uu

wa

wa

wa

uu00

0uu0

00uu

c

c

c

FAILURE ENVELOPE of UNSATURATED SOIL(INDEPENDENT STRESS VARIABLE)

b

fwa

'

faf

'

ff uuuc ff tantan

(Fredlund & Rahardjo, 1993)

134

10/22/2011

68

135

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5

Sh

ear

Str

ess,

(kg

/cm

2)

Net Normal Stress (-ua) kg/cm2)

ua-uw = 0.09 kg/cm2

ua-uw = 0.29 kg/cm2

ua-uw = 0.69 kg/cm

BH02 Neglajaya 0.5-1.0 m

c'= 0.55 kg/cm2

c'= 0.48 kg/cm2

c'= 0.38 kg/cm2

f'=26.5o

f'=26.5o

f'=26.5o

fb BH02 Neg 0.5-1.0 m 136

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

She

ar s

tre

ss,

(kg

/cm

2)

Matric suction, (ua-uw) (kg/cm2)

fb = 9.51o


fb = 26.69o

f' = 26.5o

AEV = 0.30 kg/cm2

AEV

10/22/2011

69

FAILURE ENVELOPE of UNSATURATED SOIL (EFFECTIVE STRESS VARIABLE)

137

waa uuu c '

(Khalili and Khabbaz,1998)

c : a function from soil’s ratio matric suction, related strongly to soil structure

55.0

bwa

wa

uu

uuc

Sr: Residual degree of saturationS : Degree of saturation on Critical condition

c : a function from degree of saturation (S)

(Tohari, 2002) r

r

S

SS

100c

c vs Suction Ratio138

Mspaq net c

f

f

sin3

cos6ca

f

f

sin3

'sin6M

pnet adalah tegangan rata-rata netto.

)(3 waa

net uuup c

Predicted Deviatoric Stress :

55.0

bwa

wa

uu

uuc

10/22/2011

70

139

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5

Sh

ear

Str

ess,

(kg

/cm

2)

Net Normal Stress (-ua)+c(ua-uw) kg/cm2)

ua-uw = 0.09 kg/cm2

ua-uw = 0.29 kg/cm2

ua-uw = 0.69 kg/cm2


c'= 0.56 kg/cm2

c'= 0.54 kg/cm2

c'= 0.42 kg/cm2

f'=26.5o

f'=26.5o

f'=26.5o

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5

Devia

tori

c S

tress, q

(kg

/cm

2)

Total, Effective Mean Stress, p, p' (kg/cm2)

BH01 Cilame 4.5-5.0 m

s =0.0 kg/cm2

s =0.69 kg/cm2

s =0.29 kg/cm2

BH02 Cijengkol 0.5-1.0 m BH02 Neglajaya 13.0-13.5 (ua-uw) = 0 kg/cm2

a'= 0.17 kg/cm2


'=24.5o

s =0.09 kg/cm2

M = 1.048

140

0.0

1.0

2.0

3.0

4.0

5.0

6.0

0 0.5 1 1.5 2 2.5 3 3.5 4

De

viat

ori

c S

tre

ss,q

(kg

/cm

2 )

Matric Suction (kg/cm2)

Measured

Predicted

BH02 Neglajaya 0.5-1.0 m p net : 3-ua kg/cm2

sAEV =0.30 kg/cm2

AEV

10/22/2011

71

141

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0

Devia

tori

c S

tress. q

(kg

/cm

2)

Effective Mean Stress, p' (kg/cm2)

BH02 Cij 0.5-1.0 m BH01 Cil 4.5-5.0 m BH02 Neg 0.5-1.0 m

BH02 Neg 13.0-13.5 m BH03 Neg 2.5-3.0 m BH05 Neg 0.5-1.0

CSL BH05 Neg CSL Cij 02 CSL Cil 01

CSL Neg 0.2 0.5-1.0 CSL BH02 Neg 13.0 CSL BH03 Neg

s =0.68

s =0.29

s =0.89

s =0.40

s =0.80

s =0.90

s =0.09

s =0.29 s =0.69

s =0.40

s =0.60

s =0.90

s =0.07

s =0.26 s =0.35

s =0.0

s =0.2

s =0.6

142

The evolution of peak stress over suction in p’-q’ plane of Sion Silt (Geiser 1999), in Khalili et all 2004

The evolution of CSL over suction in p’-q’ plane , kaolin soil (Wheller Sivakumar, 1995) in Khalili et all, 2004

CSL over suction in p’-q’ plane , Jossigny Silt (Cui dan Delage, 1996) in Khalili et all, 2004

10/22/2011

72

143

0

2

4

6

8

10

12

14

16

0 0.5 1

c'

BH02 Cij

unsat test

z 4.5

Zone 5

Zone 4

Zone 3

0

2

4

6

8

10

12

14

16

0 0.5 1

c'

BH03 Cij

Zone 5

Zone 4

Zone 3

0

2

4

6

8

10

12

14

16

0 0.5 1

c'

BH01 Cil

unsat test

Zone 5

Zone 4

Zone 3

0

2

4

6

8

10

12

14

16

0 0.5 1 1.5

c'

BH02 Neg

unsat test

Zone 5

Zone 4

Zone 3

0

2

4

6

8

10

12

14

16

0 0.5 1

c'

BH03 Neg

unsat test

Zone 2

Zone 3

0

2

4

6

8

10

12

14

16

0 0.2 0.4 0.6 0.8 1

c'

BH04 Neg

Zone 5

Zone 4

Zone 3

Colluvial

0

2

4

6

8

10

12

14

16

0 0.5 1

c'

BH05 Neg

unsat test

Zone 5

Zone 4

Zone 3

Colluvial

144

Wesley, 1980

RESEARCH PROGRAM : Compressibility

Kurva e-log (p)

10/22/2011

73

145

Linear Curve e-p 146

Wesley, 1980

10/22/2011

74

147

Consolidation Coefficient cv

148

10/22/2011

75

149

150

0

2

4

6

8

10

12

14

16

0.00 0.02 0.04 0.06 0.08 0.10

cv90 (cm2/det)

BH02 Cijengkol

Zone 5

Zone 4

0

2

4

6

8

10

12

14

16

0.00 0.01 0.02 0.03 0.04

cv90 (cm2/det)

BH03 Cijengkol

Zone 5

Zone 4

0

2

4

6

8

10

12

14

16

0.00 0.02 0.04 0.06 0.08 0.10

cv90 (cm2/det)

BH01 Cilame

Zone 5

Zone 4

0

2

4

6

8

10

12

14

16

0.00 0.01 0.02 0.03 0.04

cv90 (cm2/det)

BH04 Neglajaya

Zone 5

Zone 4

Colluvial

0

2

4

6

8

10

12

14

16

0.00 0.01 0.02 0.03 0.04

cv90 (cm2/det)

BH05 Neglajaya

Zone 5

Zone 4

Colluvial

10/22/2011

76

151

1. Profile Characteristic based on Bor Log, N-SPT test, and CPT Test.

2. Profile Characteristics based on CPT-u Test.

3. Profile Characteristics based on Dilatometer Test.

4. Profile Characteristics based on Pressuremeter Test.

RESEARCH PROGRAM : In-Situ Stress

SOIL PROFILE BASED ON DILATOMETER TEST

152

10/22/2011

77

DILATOMETER TEST RESULTS: ZONA 4 PARAMETER

153

154

DILATOMETER TEST RESULTS:

ZONA 5 PARAMETER

10/22/2011

78

155

DILATOMETER TEST RESULTS: ZONA 3 PARAMETER

156

10/22/2011

79

Soil Profile Based on CPT-u Test (Kalijati ,Sta.109+500, Qos Formation )

157

158

Soil Profile Based on CPT-u Test (Kalijati ,Sta.113+650, Qos Formation )

10/22/2011

80

159

PRESSUREMETER TEST PARAMETER RESULT

160

RESEARCH PROGRAM : Slope Hidrology

10/22/2011

81

161

162

10/22/2011

82

Modified Cam Clay Model 163

1. Elastic Properties2. Yield Surface3. Plastic Potential4. Hardening Rule

RESEARCH PROGRAM : Constitutive Model

MCC Simulation 164

0.00

0.20

0.40

0.60

0.80

1.00

1.20

0.00 1.00 2.00 3.00 4.00

Devia

tori

c Str

ess

q(k

g/c

m2)

Strain (%)

BH02 4.5-5.0 Neglajaya

Stress-Strain Curve

0.3 kg/cm2

0.7 kg/cm2

1.4 kg/cm2

Model Stage 2

Model Stage 3

Model Stage 1

10/22/2011

83

Structured Modified Cam Clay Model (Liu &Carter, 2002)

165

166

10/22/2011

84

Unsaturated Two Stress-State Variable Elasto- Plastic Model

167

BASIC BARCELONA MODEL (BBM),

ALONSO et al 1990

168

1.50

1.70

1.90

2.10

2.30

2.50

2.70

1 10 100 1,000

v

net normal stress p (kPa)

s = 0 kPas = 0 kPas = 29 kPas = 29 kPas = 68 kPas = 68 kPas = 89 kPas = 89 kPas = 89 kPa

s1 = 29 kPas2 = 68 kPas3 =89 kPar = 0.90b = 50 MPa-1

l (0) = 0.2l (s1) = 0.191l (s2) = 0.185l (s3) = 0.183k(0) = k(s) = 0.034

BH 01 Cij 0.5-1.0

BASIC BARCELONA MODEL (BBM)

SIMULATION

10/22/2011

85

169

0

50

100

150

200

250

300

0.00 1.00 2.00 3.00 4.00 5.00

Devia

tori

c st

ress

q (

kPa)

Deviatoric Strain e s

TXCD Unsat BH01 Cij 0.5-1 s= 29 kPa

Model BBM s= 29 kPa

TXCD Unsat BH01 Cij 0.5-1.0 s =68 kPaModel BBM s=68 kPa

TXCD Unsat BH01 Cij 0.5-1.0 s = 89 kPaModel BBM s= 89 kPa

s1 = 29 kPas2 = 68 kPas3 =89 kPar = 0.90b = 50 MPa-1

l (0) = 0.2l (s1) = 0.191l (s2) = 0.185l (s3) = 0.183M(1) = 0.59M(2) = 0.59M(3) = 0.65k(0) = k(s) = 0.034

BASIC BARCELONA MODEL (BBM)

SIMULATION

Effective Stress Elastic-Plastic Model untuk Tanah Unsaturated (Loret & Khalili, 2002)

170

10/22/2011

86

171

0.000

0.500

1.000

1.500

2.000

2.500

3.000

0.00 1.00 2.00 3.00 4.00 5.00

Devia

tor

Str

ess (

kg

/cm

2)

Axial Strain (%)

Stress-Strain curve

ua-uw = 0.29 kg/cm2 ua-uw = 0.68 kg/cm2

7 unsaturated soil and slope stability analysis_2

Documents

tvv sample soil

volume totalv water

volumetric water content

volume totalv voids

dry part

saturated soil

inco geotechnical

0peak intensity