710
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
percent increase in bending moment varying from 0.5% to 6%
with increase in H/L. On the other hand, X had a significant
effect on pile maximum bending quantified by an observed
decrease ranging between 10% and 60% with increase in X.
Positive moment observed in Figure 6 indicates reversal in
maximum moment location as described in section 2.1.
H/L has a pronounced effect on pile head lateral
deformation that is further highlighted for X equal to 2 m.
H/L and X have a insignificant effect on the maximum
bending moment in the pile with percent increase in bending
moment varying from 0.5% to 6% with increase in H/L.
-8
-6
-4
-2
0
2
4
6
8
10
12
14
0
1
2
3
4
5
6
0
0.1 0.2 0.3 0.4 0.5 0.6
Max. BendingMoment (kN.m)
Pile head deflection (mm)
Excavation ratio (H/L)
Deflection X = 2 m
Deflection X = 4 m
Deflection X= 8 m
Mmax X = 2 m
Mmax X = 4 m
Mmax X= 8 m
Pile stiffness has an insignificant effect on pile head
deflection up to H/L equal to 0.4; however, for H/L equal to
0.5, the contribution of pile stiffness is heightened due to
excessive wall and pile deflection.
Pile stiffness showed a significant influence on maximum
bending moment with maximum impact apparent at H/L =
0.5.
‐25
‐20
‐15
‐10
‐5
0
5
10
15
20
25
0
1
2
3
4
5
6
7
300
600
900
1200
Maximum Bending Moment (kN.m)
Pile head deflection (mm)
Pile diameter (mm)
Def H/L= 0.1
Def H/L= 0.2
Def H/L= 0.3
Def H/L= 0.4
Def H/L= 0.5
BMH/L= 0.1
BMH/L= 0.2
BMH/L=0.3
BMH/L= 0.4
BMH/L=0.5
Figure 6. Variation of pile head lateral deflection and maximum
bending moment with excavation ratio d = 600 mm (E
wall
I
wall
= 6.10
x10
4
kN.m
2
)
Figure 7 relationship between pile diameter and pile head deflection and
maximum bending moment (X = 2 m, E
wall
I
wall
= 6.10 x10
4
kN.m
2
).
2.4
Effect of pile stiffness
The effect of pile stiffness (expressed as pile diameter) on the
pile head lateral deformation and maximum bending moment is
illustrated in Figure 7. From Figure 7, it is observed that pile
stiffness has an minimal effect on pile head deflection up to H/L
equal to 0.4 (percent difference ranging between 2% and 10%);
however, for H/L equal to 0.5, the contribution of pile stiffness
is heightened due to excessive pile deflection (percent
difference varying from 13% to 21%). In contrast, pile stiffness
showed a significant influence on maximum bending moment
with maximum influence apparent at H/L = 0.5.
4 REFERENCES
ABAQUS 2010. User’s Manual version 6.10.
Finno R.J., Lawrence S.A., Allawh N.F. and Harahap I.S. 1991.
Analysis of Performance of Pile Groups Adjaent to Deep
Excavation.
Journal of Geotechnical Engineering
117 (6), 934-
955.
Goh A.T.C., Wong K.S., Teh C.I. and Wen D. 2003. Pile Response
Adjacent to Braced Excavation.
Journal of Geotechnical and
Geoenvironmental Engineering
129
(
4), 383-386
Kok S.T., Bujang B.K.H., Jamoloddin N., Mohd. Saleh J., and Gue S.S.
2009. A case study of passive piles failure in open excavation.
DFI
Journal
3 (2), 50-57.
3 CONCLUSIONS
Main conclusions that can be deduced from this study can be
summarized in the folllowing points:
Leung C.E, Ong D.E.L and Chow Y.K. 2006. Pile behaviour due to
excavation-induced soil movement in clay II: Collapsed Wall.
Journal of Geotechnical and Geoenvironmental Eng
132 (1), 45-43.
Distribution of lateral pile deflection along pile depth show
similar trends with pile head deflcetion in the range of 3 mm
for H/L=0.4. For H/L=0.5, wall undergoes rotation causing
excessive lateral deflection in pile and transformation in the
pile deflection profile.
Miao L.F., Goh A.T.C., Wo N.K.S. 2006. Three-dimensional finite
element analysis of passive pile behavior,
International Journal for
Numerical and Analytical Methods in Geomechanics
30, 599-619.
Profiles of bending moment distribution along pile length
show single sided parabolic distrition; however, when
excessive deformation occurs (i.e., at H/L=0.5) reversal in
bending moment distribution was observed. The degree of
bending moment reversal is highly dependent on distance of
pile from supported excavation (X) and pile stiffness (d).
Ong D.E.L, Leung C.E. and Chow Y.K. 2006. Pile behaviour due to
excavation-induced soil movement in clay I:Stablewall.
Journal of
Geotechnical and Geoenvironmental Eng
132(1), 36-44.
Pan J.L., Goh A.T.C., Wong K.S. and Selby A.R. 2002. Three-
dimensional analysis of single pile response to lateral soil
movements,
International Journal for Numerical and Analytical
Methods in Geomechanics
26 (8), 747-758.
Wall stiffness (E
wall
I
wall
) has minimal effect on pile head
deflection and maximum bending moment for H/L < 0.30.
However, for H/L > 0.30, the wall stiffness effect was more
pronounced.
