Geoscience Reference
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The ICL (intrinsic compression line) curve, corresponding to equation [5.28] and
represented by Figure 5.19b, can then be deduced from a statistical model based on
the experimental curves passing through the two specific points ( σ ' v = 100 kPa,
I v = 0) and ( σ ' v = 1,000 kPa, I v = -1). σ ' v is expressed in kPa.
=
2.45
1.285 log '
σ
+
0.015 (log ' )
σ
3
[5.28]
V
an e e for the “arrangement of grains” are,
on the other hand, connected by [5.29] to e L , the void ratio corresponding to the
liquid limit - the only parameter for the “nature of grains”.
The two particular parameters
*
*
100
1000
=
*
0.109
+
0.679
0.089
2
+
0.016
3
100
*
L
L
L
[5.29]
Ce e
=− =
*
*
0.256
e
0.04
1 0 0
1000
L
Although both approaches by Biarez and Burland appear to be based on a similar
method, there is a fundamental difference in the manner in which the intrinsic
characteristics of the “arrangement of grains” were defined on the oedometric path.
Burland used two experimental values ( *
an e e ) for the “arrangement of
grains”. On the other hand, Biarez, by introducing I L , used two parameters of the
“nature of grains” ( e L and e P ). Both models link the “nature of grains” parameters to
the “arrangement of grains” parameters, however, using statistical correlations under
oedometric loading. This corresponds to relation [5.2] in Biarez's model and to
relation [5.29] in Burland's model. We can deduce that
*
100
1000
*
and
*
are nature
100
1000
parameters in Biarez's method.
Biarez
C c
C c *
1.4
Experimental values
wLvarying from 25 to 159,3%
(Burland, 1990)
Burland correlation (Cc*)
B&F correlation (Cc)
B&F
3
Biarez
e * 100
1.2
Burland
2.5
Burland
1
2
0.8
(b)
1.5
0.6
-a-
1
0.4
0.5
0.2
0
0
0.5
1.5
2.5
3.5
4.5
5.5
0 .5
1 .5
2.5
3.5
4.5
5.5
1
2
3
4
5
6
e L
e L
0
1
2
3
4
5
6
Figure 5.20. Variation of C c , C * c and e * 100 parameters as fonction of e L
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