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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
and the results are therefore highly dependent on the
permeability anisotropy in the clay of interest. For instance, if
, the consolidation rate might be overestimated.
4 CONCLUSION
Although they may capture the nature of the smear zone more
realistically, the impacts on the assessment of
of the more
complex models (III-VI) rather than model II are insignificant
under the assumptions made in this study and, as argued by
Onoue et al. (1991) and Hird and Moseley (2000), model II
(Hansbo 1979) is still useful for practical engineering purposes
due to its simplicity. This study shows that the even more
simple model suggested by Kjellman (1949), neglecting the
smear zone but adopting
instead of
, might give
satisfactory results. Care should however be taken, as
assessments using this model are dependent on the permeability
anisotropy in the clay of interest.
It is the authors
’
opinion that it is more important to put an
effort into reducing the uncertainty in
(or
for use in model
I) than trying to investigate
and
in ordinary engineering
projects. It is also important to consider the change in
that
occurs as a result of the decrease in void ratio as consolidation
of the clay proceeds (e.g. via model III).
5 ACKNOWLEDGEMENTS
The Tyréns Foundation is acknowledged for funding this study.
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Figure 3. The influence on
of
and
for
1.6 metres.
Figure 4. The contribution to
of the variances in
,
,
and
⁄
.
0
0.2
0.4
0.6
0.8
1
0
0.2
0.4
0.6
0.8
1
(-)
(-)
Hansbo (1979), II
Indraratna et al. (2005), III
Walker & Indraratna (2006), IV
Basu et al. (2006)-b, V
Basu et al. (2006)-d, VI
0
0.2
0.4
0.6
0.8
1
(-)
