Unit Cell Testing of Reinforced Soils - Reinforced Soil Engineering: Advances in Research and Practice - page 44

Figure 5 Continued.
Figure 5b compares the measured strength with the modified and original
equations. Figure 5c shows the predictive capability of Eq. (12) compared to the
tensile load. Note again that this method is based on the crude approximation, and
a further development cannot be expected. A more rigorous method of analysis
can be performed using the stress characteristics method (Sokolovskii, 1956) as
has been performed by Tatsuoka (1986b).
Holtz et al. (1982) performed both short- and long-term tests on sandy soil
reinforced with geotextiles. In addition to the strength, they also looked into the
deformation modulus of reinforced soil specimen. The strength and deformation
modulus were increased due to reinforcement. However, at higher confining
pressure, the initial modulus decreased by reinforcing. Holtz et al. (1982) did not
explain the reduction in the initial modulus with confining pressure, but the
author regards this as a consequence of the isotropic consolidation prior to
shearing, as discussed subsequently.
2.2 Plane Strain Compression Test
The above-mentioned studies were based on a cylindrical soil specimen, which
does not closely simulate most of the field stress conditions, namely plane strain.
McGown and Andrawes (1977) studied reinforced sand using a plane strain