Geosynthetic Reinforced Containment Dike Constructed over Soft Foundation: Numerical Analysis - Reinforced Soil Engineering: Advances in Research and Practice - page 282

Table 3 Anisotropic Model
Parameters for Strata 1 and 2

Parameters Values

l 0.36

k 0.04

n 0.20

M c (M e ) 1.20 (1.02)

R 3.4

C 0.4

s 2.0

C 1 5.0

C 2 1.0

C 3 5.0

W 2.0

A 0 1.0

adopted in the two-dimensional plane strain analysis are summarized in Table 4.
This equivalent model produced results within 5% error with the actual
axisymmetric idealization at 90, 180, and 360 days after load application (20 kPa
as step loading at t 0). The sand layer and dike fill were assigned a relatively

high coefficient of permeability—namely 200m/day—to simulate free drainage.
The initial stress states for the several soil layers in the underlying strata
were calculated using the given unit weights for saturated soils (see Fig. 2 ) , the
thickness of the layers and coefficient of earth pressure at rest K 0 , which was
assumed as 0.6 for all clay layers.
For the purpose of comparison of the proposed model with the isotropic
bounding surface model of Kaliakin and Dafalias (1990a,b), a finite-element
analysis was also conducted by assuming the clays to be isotropic and time-
independent by taking the material constant A 0 to be 0.0. Table 5 summarizes the
parameters for above two cases of analysis.

¼

Table 4 Coefficients of Permeability of Foundation

Coefficient of
permeability
( £ 10 2 3 m/day)

Strata 1 Strata 2A

With drains No drains With drains No drains Strata 2B

Vertical 3.8 3.8 3.8 3.8 0.61

Horizontal 4.2 1.7 4.2 1.7 0.61