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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
This report is organized into several major topics and subject
areas, as follows: site characterization (4 papers), technological
advances (9 papers), geotechnical analyses and behavior (14
papers), and soil and rocks properties (15 papers), leading to a
total of 42 papers. The main objective is to present an overview
and the advances on the main addressed topics of this
Conference Session, hence summarizing and emphasizing the
important contributions from the papers.
Table 1 presents a summary with the main topics and
subtopics addressed for each of the listed papers, together with
the adopted investigation tools (in-situ or laboratory), the main
soil type, the investigation approach, and a short 1-line
summary of the paper’s prime objective & contribution. Given
such cited divisions, the papers will be reported under each of
the defined topics and subtopics, as it follows next.
2. SITE CHARACTERIZATION
In this Conference Session, four papers dealt with site
characterization; two of them are related to soil classification
and the other two are more focused on geotechnical modeling.
2.1. Soil classification
The paper written by
Serratrice
proposes a classification
method for natural soils based on piezocone test data. Two
aspects are considered to classify the soils with liquefaction
potential, the drained and undrained strength via triaxial tests
and the soil’s density. The method is presented and applied in
two examples where CPTU data are available in homogeneous
clayey deposits.
The paper from
Baud & Gambin
presents a contribution to
enhance the Pressiorama
®
diagram with the extra rheological
factor “
”, which was originally introduced by Ménard on his
design method. The authors used very good quality self-bored
PMT tests (STAF technique) in several soil types, from soft
clays to rock to obtain E
M
/p
*LM
values. They proposed a re-
evaluation of the rheological factor
and the findings are given
by an equation graphically expressed in the Pressiorama
®
.
2.2. Geotechnical modeling
The paper from
Ivšić et al.
discusses the applicability of the
RNK-method for spatial engineering & geological and/or
geotechnical modeling. This method was tested on many
landslides in Croatia and it allows the differentiation of the
minimum shear strength zone, or regions of different hydraulic
conductivities and varied soil densities. The proposed model
was verified by measurements of lateral movements in the
landslide area and by results of stability analyses. They
concluded that the RNK-method can be used in the study of
landslides and slope stability by searching the zone of minimum
shear strength.
The paper from
Steenfelt et al.
presents the use of in-situ
and laboratory tests for site characterization on an important on-
going infrastructure project in China. A very extensive site
investigation campaign was carried out comprising geotechnical
boreholes, CPTUs and seismic testing with associated advanced
laboratory testing. The paper described the results and the
interpretation technique used to provide ground stratification
and stiffness variations to be used in design. They concluded
that the CPTU was a important tool for a clear geological unit
delineation, which also allowed a robust and safe design.
3.
TECHNOLOGICAL ADVANCES
In this Conference Section, nine papers were selected to be part
of the technological advances (main) topic; three of them
presented new uses of in-situ testing technologies and six dealt
with new types of in-situ testing tools (or apparatuses).
3.1. New uses of in-situ technology
Kim´s et al.
paper has an environmental appeal since it deals
with the geological CO
2
sequestration as an effective mean of
reducing the emissions of carbon dioxide. The problem pointed
out in the paper is that forward strategies and technologies of
CO
2
sequestration in Korea need to be specified depending on
the geological conditions of potential sites (in Korea). The
authors reviewed the geological characteristics of CO
2
storage
projects around the World and also discuss the suitability for
CO
2
sequestration. A systematic and quantitative evaluation
method to assess the storage and economic efficiencies of
sedimentary basins in Korea using dimensionless values
between 0 and 1 was applied (Figure 4). The paper also
discusses the potential of using geophysical tests to assess the
suitability of field strata for CO
2
-storing, and to monitor CO
2
movement and possible leakages.
Figure 4. Score for suitability for Korean sedimentary basin
(Kim et al)
.
The paper from
Fenton & Hicks
discusses the uncertainty
associated with site characterization and it focused specifically
on the effect of number of samples on residual uncertainty. The
results can be used to quantitatively select the required number
of samples needed to achieve a target maximum residual
uncertainty level. A statistical approach was used to study this
problem and it was concluded that the accuracy improves as the
number of samples and the correlation length increases.
Somasundaram
et al.
present the characterization and
settlement modeling of deep inert debris fills. Inert fills can be
considered as a non-text book type geomaterial since they are
difficult to characterize and model by current geotechnical
methods, due to their inherent heterogeneity, very large particle
sizes, and nested and voided structure. The authors presented an
approach to characterize a 54 m deep inert debris fill, to model
its settlement behavior under seismic loading and groundwater
level rise, and to develop remedial measures to render it suitable
for development.
3.2. New in-situ tools
Jacquard´s et al.
paper presents a new probe to overcome the
limitation of Menard type pressuremeter tests, i.e., the difficulty
of reaching large expansion volumes and pressures. This new
device allows for the volume of the hole to be doubled, even
under high pressures. The authors described the technological
innovations that increased the capabilities (and reliability) of the
pressuremeter probe as well as presented comparative tests on
different sites to demonstrate the advocated technical advance in
this enhanced PMT device.
In
Rito & Emura
paper a new type of sampling method
called ‘
Koken wire line system
’ is developed (Figure 5) to
retrieve high depth undisturbed samples in deep Pleistocene
clay and sand layers at the Kansai International Airport area.
The authors also developed two different pore pressure
measuring devices, and concluded that both the sample quality
and the measured values were respectively of high quality and
with reasonably good accuracy to be used in the settlement
design of the subsoil of this airport, in Japan.
