Civil Engineering Reference
In-Depth Information
Figure 2.9
Effect of relative density, based on field data. (After Skempton, 1986.)
◦
Figure 2.10
Variation of
φ
−
φ
cv
; with relative density: (
) triaxial; (
) plane strain; mean effective
stress (p
) 150 to 600 kN/m
2
;
φ
measured as secant value. (After Bolton, 1986.)
vane shear tests, or from laboratory triaxial compression tests on carefully taken
undisturbed samples). It is generally necessary to employ thin-walled piston samples
for this purpose. Such samples may also be used for laboratory determination of the
shear strength of the clay in terms of effective stress to permit the preferred calculation
of downdrag by effective stress methods.
