Verti

cal S

train

, � v

(%)

0

5

10

15

20

25

()

( )

( )

( )�' �' p ( )

OED 8 EI.9.5 Possible

Curve

0.19 constant

0.48

0.2

0.18

CRS 24 EI.55.1 OCR = 3.20

CRS 19 EI.4.0 OCR = 1.12

vo CR

0.1 1 10 100Vertical Effective Stress, �' (KSF)v

Typical I-D Compression Curves for Blue Clay at SB Site Note: See section 3.1 of part IV - 3 for description of CRS consolidation test

50

40

30

20

10

0

�',

(deg

rees

)

Mexico City Clay Altapulgite

Soft Clays

Shales Clay Minerals

Fri

ctio

n A

ng

le,

Fig. 19.7 TPM (1996) Soft and Stiff Clays

0 10 20 30 40 50 60 70 80 90 100 200 400

Plasticity Index, Ip (%)

Dep

th, z

(m)

Profile Indices Stress History (kPa) 0 10 20 30 IP

0 1 2 3 IL 100 200 3000

Desiccated Crust2 due to freeze - thaw cycles 4

6

8Quick Clay

10 St = 200 + 100)

12

(high IL

Cementation:-' > High � p for such high

14 values of IL

16 > Very brittle behavior a` la sheet AS

18

20

�` p

�' poU

Ip(%)

IL �'

Till

Crust

Selected Profile

From erratic data

on Block Samples CK

Test Locations

Marine

Lacust­rine

Clay

Clay

vo

0

0

4

8

12

16

20

24

4

8

q/�

�` p

�` p�`

`p

B - 6

Probable

Min.

Min. Radius

Casagrande Construction

Max

vo

0.5

0.4

Verti

cal S

train

, � v(%

) Ve

rtica

l Stra

in, �

v(%)

0

�' �' p

Ip L

�` �` p<

�` �` p

vo = 60 kPa, = 145 - 150 kPa

= 16%, I = 1.3

AT z = 6.3m

vc

Intact

vc Laboratory

In Situ

0.34 0.80 1.33

Destructured

0 1 2 3 4 5 6 7 8

0.3

0.2

0.1

Axial Strain, �a(%)

(a) Normalized Stress-strain Data From CkoUC Tests

0.5

26 10 20 40 100 200 400 1000 0.4

Log Scale �v̀c(kPa) 0.3

(a) Semi log scale Kc = 0.55rg trai C

at in sit

esp at insitu

int tyielde l

�` �` p/

�

�' p

Destructured Yield Envelope La e S n T

u OCR

TC OCR

ac

nve ope

vc

' = 35

q/ �

' p

0.2

12

16

20

�` p �`IP(%) IL

9

�` p �` >

/

B - 6

vo James Bay B-6 Marine: Block

AGS CH Marine: Tube

Symbol Sample

2.8 95

85 0.6 42

vo James Bay: Cementation AGS CH: Mechanical and or desiccation

Note: Most likely mechanism causing

0.1

0

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 p`/ �'p

( )

( ) �` �` p �` p� r( )/

( )

AT IN SITU OCR :

NORMALLY CONSOLIDATED :

Triaxial Compression TC

Triaxial Extension TE

vc LAB IN SITU : Peak q TC

TC and TE Destructured

(a) Normalized Effective Stress Paths and Yield Envelopes 100 200 300 400 500 600 700 800

B - 6 Undrained shear - very brittle behavior, i.e. small �fConsolidation Stress, �'vc (kpa) followed by high rate of strain softening

(b) Natural scale B - 6 1-D compression - sharp break in �v vs log�'vs & S-shaped virgin compression

Adapted from Jamiolkowski, Ladd, Germaine & Lancellota (1985) 11th ICSMFE, San Francisco

0