Geoscience Reference
In-Depth Information
800
600
700
500
600
400
500
simulation: Rn=0.45
test: Rn=0.45 (Fioravante 2002)
simulation: Rn=0.01
test: Rn=0.01 (Fioravante 2002)
400
300
300
200
200
simulation: Rn=0.45
test: Rn=0.45 (Fioravante 2002)
simulation: Rn=0.01
test: Rn=0.01 (Fioravante 2002)
100
100
0
0
0
10
20
30
40
50
0
10
20
30
40
50
s/d (%)
s/d (%)
(b)
(a)
Figure 9.27.
Force-displacement curves for the Toyoura sand (
I
D
=0.07
)
([FIO 02] and [DAG 08]). Results are obtained for
two interface rugosities
R
n
=0.45
and
0.01
. (a) shaft; and (b) base
0
4
−1
3.5
−2
3
β
=
τ
s
/
σ
vo
−3
2.5
−4
2
z=0.89 m simul.
z=2.89 m simul.
z=4.39 m simul.
z=6.39 m simul.
z=0.9 m measured
z=2.7 m measured
z=4.6 m measured
z=6.4 m measured
1.5
−5
1
−6
0.5
−7
simulation: Rn=0.45
experimental: Rn=0.45
curve:Fioravante 2002
0
−8
−0.5
−9
0
10
20
30
40
50
0.5
1
1.5
2
2.5
3
3.5
s/d (%)
β
(a)
(b)
Figure 9.28.
Comparison of computed and measured mobilized shear for a rugous
interface
R
n
=0.45
. (a) Evolution of
β = τ
s
/σ
v0
with relative settlement at
the head of the pile (
s/d
); and (b) Evolution of
β
with depth for
s/d = 25%
The importance of this state parameter can also be seen in the study of the loading-
unloading behavior, which highlights notions such as residual stress and cyclic fatigue.
If we unload an already loaded pile up to a high level of mobilized friction, we
will find that, after the total force on the pile head has been suppressed, the residual
stresses can be trapped inside the soil at the top and around the pile. The amplitude
Search WWH ::
Custom Search