Example of Laboratory Test Data. Figure 8.3 presents results of consolidation tests performed on
two specimens of Orinoco clay at a depth of 128 ft (40 m) (Ladd et al., 1980; Day, 1980). The upper
plot is known as the consolidation curve for the two Orinoco clay soil specimens. The horizontal axis
is the effective consolidation stress (i.e., the applied vertical pressure) which is designated s′ vc, with
the subscripts vc referring to vertical consolidation pressure and the prime mark indicating that it is
an effective stress. Note that the horizontal axis is a logarithm scale. In Fig. 8.3, the vertical axis is
percent vertical strain ev. The vertical axis could also be in terms of the void ratio e.