ABSTRACT
Geophysical methods can be used for establishing
soil and rock stratification, but also for determining
geotechnical properties by direct or indirect
methods. The application of different geophysical
methods for geotechnical site characterization is
discussed. Finally, new trends and developments of
geophysical site characterization are presented.
INTRODUCTION
The goals of geotechnical and geophysical site
characterization (GSC) are to provide the
geotechnical engineer (designer, contractor, owner
or authority) - based on the results of field
investigations - with sufficiently detailed
information in order to plan, design, construct and
operate structures on or below the ground.
GSC has become one of the most important and
rapidly developing areas of geotechnical
engineering. In order to facilitate the development
of new field investigation methods and their
practical applications, the International Society for
Soil Mechanics and Geotechnical Engineering
(ISSMGE) sponsors two technical committees (TC
10 and TC 16), focusing on geophysical and
geotechnical site characterization, respectively.
While the benefits and limitations of conventional
geotechnical field investigation methods are
generally understood and accepted by the
profession, this is not the case - in the eyes of many
geotechnical engineers – with respect to geophysical
methods. These are still associated with a flair of
“mysticism”.
One reason may be the lack of understanding of the
advantages and limitations of different geophysical
methods (often unjustifiable expectations, which can
not be satisfied), another the sometimes high degree
of empiricism and judgement in connection when
interpreting data. A third factor may be the lack of
correlation between measured values and the
anticipated geotechnical parameters. However,
during the past decades, geophysical methods have
become highly scientific tools, especially as a result
of the powerful electronic measuring and data
acquisition systems, sophisticated date interpretation
and presentation methods. Today, geophysical
methods are widely used in many different technical
and other disciplines, Table 1.