Environmental Engineering Reference
In-Depth Information
Figure 11.18.
Predicted construction pore pressures vs total vertical stress for Yonki Dam using
Vaughan method.
Figure 11.19.
Observed construction pore pressures for Yonki Dam - courtesy of the Snowy Mountains
Engineering Corporation.
1
is the total vertical stress in excess of the threshold pressure, e.g. for c
In this
0,
30° and
u
2°; slope of curve
0.9, “x” intercept
3.23S
u
.
Hence if the dam is constructed so that Su
80 kPa, the predicted pore pressures
would be as shown in Figure 11.18.
In practice there are negative pore pressures in the embankment below the threshold
pressure and the slope of the curve increases with increasing vertical stress. Figure 11.19
shows results from Yonki Dam.
11.4.2.4
Estimation of pore pressures using advanced theory of partially saturated soil
Fry et al. (1996) present a good overview of the state of art of application of partially sat-
urated soil mechanics to embankment dams and slope stability up to 1996.
