Centrifuge Modeling of Seismic Performance of Reinforced Earth Structures - Reinforced Soil Engineering: Advances in Research and Practice - page 414

Table 3 Types of Loading to Reinforced Earth and Methods Simulating Loadings

Examples of previous
studies using methods

Type of loading Simulating methods

Construction of wall Increasing centrifugal

acceleration

Bolton and Pang (1982)
Shen et al. (1982)
Mitchell et al. (1988)

Removal of temporary
support under constant
centrifugal acceleration

Davies and Jones (1998)
Matichard et al. (1988)

Surcharge from the top Supplying water into box

with flexible base

Mitchell et al. (1988)

Hydraulic piston with
loading plate

Taniguchi et al. (1988)

Seismic force Tilting methods Taniguchi et al. (1988)

Shaking table Satoh et al. (1998)

Takahashi et al. (1999)
Takahashi et al. (2001)

removed temporary supports in front of the reinforced slopes under a constant
centrifugal acceleration field. Also, applying external loads like surcharge and
seismic force to the model reinforced earth structures with reasonable static
stability under a constant acceleration is the most appropriate situation where
controlled initial conditions and loading conditions can be specified. However, it
should be noted that even in this type of test the effect of construction sequence is
inevitably included in the initial conditions of reinforced soil as shown in Fig. 2.

Particle Size Effects. If the same soil as the prototype is used in the
model, the difference of the scaling factors between the model dimensions and
soil particle size cannot be avoided, as shown in Table 1 . The effect is called
“particle size effect,” which should be considered when the particle size would
be significant compared with model dimensions and local effects of soil
particles would influence the behavior of soil, such as shear band formation in a
small model (Tatsuoka et al., 1991). These conditions may most probably occur
in the pullout failure of geogrid reinforcement. If the dimensions of the geogrid
are precisely reduced in the model, the sand particle size becomes relatively
large compared to the typical dimensions of the geogrid, like the opening size
and thickness. To answer the question about the particle size effects, Satoh et al.
(1995) conducted pullout tests in dense Toyoura sand using real geogrids and a
reduced-size model geogrid made by the same procedure as the real one.
They obtained similar relationships between the pullout forces normalized by