Download Three-Dimensional Finite-Element Program to Predict the Behavior

Consequently, the shaft is 60 inches in diameter and subject to six 200-psi (see Figure
5.10) load increments (total 1200psi).
The clayey-silt soil is characterized with a C of 25 psf and a φ 270. In the case of
triaxial extension loading (horizontal stress diminishing), Sandler and DiMaggio’s
Strength Parameters α and θ are given by:
α=
6 c cos φ
3 (3 + sin φ )
θ=
2 sin φ
3 (3 + sin φ )
(5.2)
Using c of 25 psf and φ of 270 gives a α of 4.25 and a θ of 0.15, approximately.
Shown in Figure 5.11 are the vertical displacement (PlasPLOT file: shaft.prb) of
the drilled shaft and surrounding soil subject to increasing vertical stresses. The top left
Figure 5.11 Vertical Displacement of Drilled Shaft and Surrounding Soil
100