Geotechnical News December 2011
23
GEOTECHNICAL INSTRUMENTATION NEWS
Geotechnical Instrumentation News
John Dunnicliff
Introduction
This is the sixty-eighth episode of GIN.
Two articles, a report on the recent
FMGM and a book review this time.
The Once-every-four-years
Gathering of our Clan
The 8
th
International Symposium on
Field Measurements in GeoMechanics
(FMGM) in Berlin, Germany, is now
done and dusted. Here’s a report by
Ton Peters, a colleague from The
Netherlands. There were some very
useful practical papers, including many
on recently developed remote methods
for measuring deformation, including:
• Terrestrial interferometric synthetic
aperture radar (TInSAR, GBIn-
SAR)
• Satellite interferometric synthetic
aperture radar (SInSAR, including
DInSAR and PSInSAR)
• Robotic Total Stations (RTS or
ATS: Automatic Total Stations, or
AMTS: Automated Motorized To-
tal Stations)
• Terrestrial Laser Scanning (TLS)
• Airborne Laser Scanning (ALS or
Aerial LIDAR)
• Digital photogrammetry
• Digital image correlation
I’m planing to provide an overview
of each of these and other remote meth-
ods for measuring deformation in one
or more later GIN—a one-page over-
view of each and a concluding article
with a comparative analysis of the vari-
ous techniques.
As indicated by Ton Peters in his
report, a hard copy of the symposium
proceedings will be available from ear-
ly December 2011:
• Publisher: TU Braunschweig
• Editors: J. Gattermann and B. Bruns
• ISBN: 3-927610-87-9
• For further information:
If you’re a serious member of our
intrumentation clan, I encourage you
order a copy.
The 2015 FMGM will be in Austra-
lia, and 2019 FMGM may be in Brazil.
Evaluating Practices for
Installation of Vibrating Wire
Piezometers
In past GINs we’ve had several
articles in support of the fully-grouted
method for installation of vibrating
wire piezometers. Garrett Bayrd of
Shannon and Wilson, Seattle, has
faced reluctance by decision-makers
to adopt this method, despite all the
evidence in GIN and elsewhere. He has
therefore undertaken a test program to
evaluate the necessity of a variety of
installation procedures, and to check
the accuracy and response times of
vibrating wire piezometers installed
in different materials. His intent was
to see if simpler installations could
function as well as more complicated
ones. In addition to reporting on his
test methods and results, he includes
an overview of previous publications
about the fully-grouted method,
including two that were presented at
FMGM in Germany in September. His
conclusions add more ammunition for
us when we advocate use of the fully-
grouted method.
Case History Describing a
Distributed Fiber-Optic
Monitoring System
Past GINs have also included two
articles on the distributed fiber-optic
system (Inaudi and Glisic, September
2007; Bennett, December 2008). Bill
Shefchik of Burns & McDonnell,
Kansas City and his colleagues provide
a case history describing use of the
method for providing early warning
of sinkhole formation over deep
caverns created by salt mining. There
were several papers on measurement
with fiber-optic sensors at FMGM in
Berlin—emphasizing my suggestion
that you might want to have a copy of
the proceedings.
Monitoring Underground
Construction—A Practice Guide
There is a new and excellent “practice
guide”, focused on monitoring
underground construction but, in my
view, relevant to all other types of
geotechnical construction for which
monitoring may be of value. See the
book review later in this GIN.
The Next Continuing Education
Course in Florida
This is now scheduled for April 7-9,
2013 at Cocoa Beach. Details of this
year’s course are on
.
dce.ufl.edu/geotech. The 2013 course
will follow the same general format
but with significant updating, including
remote methods for measuring
