Behaviour of soil before failure - The Mechanics of Soils and Foundations - page 174

Figure 11.13 State paths in undrained tests - Example 11.1.

Table 11.1 Yield and critical states in undrained tests - Example 11.1

Sample Initial state Yield point Critical state

p 0 q y p y q f p f v 0 v y v f

(kPa) (kPa) (kPa) (kPa) (kPa)

A 600 1.97 0 600 1.97 294 300 1.97

B 400 1.97 280 400 1.97 294 300 1.97

C 150 1.97 260 150 1.97 294 300 1.97

Example 11.2: Determination of state path and yielding Three further samples D, E
and F of the soil described in Example 11.1 were prepared at the same initial state
as samples A, B and C. Each sample was tested drained following a stress path with
increasing q with p held constant.
The state paths are shown in Fig. 11.14. When the state is inside the state boundary
surface the behaviour is elastic and shearing and volumetric effects are decoupled; hence
δ

0 for constant p stress path tests. The states of the samples after compression and v =

Figure 11.14 State paths in drained tests - Example 11.2.