Geoscience Reference
In-Depth Information
Table 5
Isotropic Model Parameters for Strata 1 and 2
Parameters
Isotropic, time-independent
Isotropic, time-dependent
l
0.36
0.36
k
0.04
0.04
n
0.20
0.20
M
c
(M
e
)
1.20 (1.02)
1.20 (1.02)
R
2.0
2.0
C
0.4
0.4
s
2.0
2.0
C
1
5.0
5.0 (h
2
)*
C
2
1.0
2.0 (m)*
C
3
5.0
5.0 (h
c
)*
W
2.0
1.0 (w)*
A
0
0.0
1.0 (a)*
n
—
2.0
V
—
7.9E
þ
9 (kPa.min)
S
v
—
1.6
*
See Kaliakin and Dafalias (1990a,b) for definitions.
5 RESULTS AND DISCUSSION
representative locations between the analysis and field measurements. The
settlement was for the point at a depth approximately 3.3m below the surface and
1.8m to the left of the centerline of the dike. The horizontal displacement
distribution was for the vertical line at 6.7m to the left of the centerline. Due to
the simplified method used to simulate the water flow, it required another set of
finite-element analysis to obtain the curve of pore pressure response with time.
The results of comparison showed that the agreement between model
prediction and measurements is satisfactory. However, the analysis under-
estimated the horizontal displacement, especially for the isotropic model. The
difference between the anisotropic model and field measurements could be
partially attributed to the idealization of three-dimensional to two-dimensional
configuration. Also, the difference between designed and constructed cross
section contributed to the difference. Moreover, the recorded deformation was
large, whereas the analysis assumed small strain deformation.
The results also showed that the anisotropic bounding surface model gave a
better prediction than the isotropic version of model. Anisotropy played an
important role in determining the response of the foundation under embankment
loading. Ladd et al. (1994) have indicated that the conventional isotropic version
Search WWH ::
Custom Search