Civil Engineering Reference
In-Depth Information
one-dimensional compression and swelling will have to take account of the shear
stresses. The link between these can be developed by going back to Sec. 3.2. From
Eqs. (3.3) and (3.4) with
σ
a
=
σ
z
and
σ
r
=
σ
h
, and making use of Eq. (8.13),
we have
q
=
σ
z
(
1
−
K
0
)
(8.16)
p
=
1
3
σ
z
(
1
+
2
K
0
)
(8.17)
Figure 8.12 shows the behaviour of soil in isotropic and one-dimensional compression
and swelling together; the subscripts 1 refer to one-dimensional behaviour. These
show normal compression lines OACD and O
1
A
1
C
1
D
1
with the same gradients
λ
and values of
v
at
p
=
1 kPa of
N
and
N
0
. The swelling and recompression
lines ABC and A
1
B
1
C
1
have approximately the same gradients,
κ
, and the same
yield stresses,
p
y
, but different values of
v
κ
. (The gradients
are actually slightly
different because the value of
K
0
changes during one-dimensional swelling and
recompression.)
κ
Figure 8.12
Soil behaviour during isotropic and one-dimensional compression and swelling.
