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International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
total number of descriptors,
n
is the descriptor number,
M
is the
total number of points describing the boundary,
m
is the index
number of a point on the boundary,
Z
n
is the Fourier descriptor
and
i
is the imaginary number.
Each Fourier descriptor, especially those of the lower order,
are associated to specific and morphological features of the
particle shape.
The average shape descriptors obtained for a reasonable
number of grains taken from each sand sample are shown in
Figure 7.
A clear more unevenness in the boundary of the Zandvoort
grains can be recognized due to the higher contribution of
higher order Fourier descriptors to the shape morphology.
5 CONCLUSIONS
The calibration of relationships between real and laboratory
scale treatment may support soil mixing QC/QA procedures.
In sandy soil, laboratory specimens tests results may be
lower than that obtained by wet grab samples due to water loss
during in situ mixing operations.
The results show that quite a good match may be achieved
by simulating in laboratory the in situ water drainage.
The results obtained from the newly developed experimental
apparatus show that the kind of sand may greatly influence the
water drainage effect on the mechanical properties of the
stabilized soil.
The different degree of angularity of the grains and the
different nature of the minerals composing the two sands
considered in this study should be considered as relevant factors
affecting the performance of the stabilized soil, as well as the
grain size distribution.
Further study are needed to validate and extend the results
and findings described in this case history.
To simulate in situ condition it is also necessary to carefully
take into account other possible factors such as: mixing energy,
use of compressed air, molding technique and curing conditions.
6 AKNOWLEDGEMENT
The authors would like to thank the Hoffman Group and the
Bauer Group, especially Mr. Franz Werner Gerressen & Mr.
Thomas Vohs for kindly providing the construction data for this
study.
The authors wish to thank Mr. Fabrizio Tocci for his help in
conducting the laboratory test at the Department of Civil,
Environmental and Architectural Engineering of Sapienza
University of Rome.
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