671017.pdf

Surcharge blocks

Retaining wall (le) Retaining wall^ (right)

Slope lls

I^1

SN 15

SN 14

SN 13

SN 12

SN 11

I^2

SN 25

SN 24

SN 23

SN 22

SN 21

A

A

012

(m)

+96.^55

+91.^80

(a) Plan view

012

(m)

Recharge tren ch Crest blanket

SN 13

Strain gauge (SG )

Inclinom eter

Granular material

Blinding layer 75 mm

with A 252 mesh

I 1

I 2

SG -1

SG -1 SG -2

SG -2 SG -3

SG -3

SG -4

SG -4

SN 23

Slope lls

A layer of asphalt betw een

blinding and drainage layer 91. 80

96. 55

Drainage layer 150 mm

no- nes concrete

Toe apron

Section A-A

(b) Section view

Figure 1: General arrangement of the field test.

acceleration;k푤is the pore water flow velocity;nis the out-

ward normal to푆;휌푤and휌푤^0 denote the water density and a
reference density for normalization, respectively.
The coupling stress equilibrium and flow continuity equa-
tions are solved simultaneously. A Lagrangian formulation is
used in the discretization of the balance equation for the soil
skeleton, and displacements are taken as nodal variables. The
continuity equation is integrated in time using the backward
Euler approximation method, and pore water pressure is
taken as a field variable in finite element discretizations.

Generally nonlinearity arises from the coupling between

seepage and mechanical behavior in the system equations.

The Newton-Raphson method is used to calculate the incre-

mental numerical solutions. In addition, Darcy’s Law is

appliedtomodeltheporefluidflow,whichhasbeenshownto

be valid for unsaturated soils if the coefficient of permeability,

k, is written as a function of the degree of saturation.

3.2. 3D Finite Element Mesh and Boundary Conditions.The

symmetry of the nailed slope and load/boundary conditions