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Geotechnical News • June 2013
www.geotechnicalnews.com
GEOTECHNICAL INSTRUMENTATION NEWS
of a complete instrumentation plan,
with more than one instrument type.
This permitted cross checking of criti-
cal readings across different instru-
ment types that aided in determining
a problem with the inclinometer data.
The surveying of the top of casing
allowed for combined readings to
provide a more complete representa-
tion of what was happening above
and below surface. The deep monitor-
ing points and MPBXs also provided
additional redundancy and means of
correlation.
Lesson learned 2: Communication
and education of needs.
During installation of the borehole
inclinometers, there was a lack of
understanding of what was required
for a successful installation. The field
personnel and engineer should have a
clear understanding that the instrument
should be installed in a stable stratum
and what to expect and look for dur-
ing the drilling of the borehole. If the
field conditions differ than expected,
communication is important to modify
procedures as required to ensure
expectations are met.
Lesson learned 3: Be adaptable to
the project and client needs.
This case history documents an
example of a monitoring problem that
occurred after installation and well
into the construction project. However,
some innovative thinking was able to
provide a solution so that subsurface
movement of the wall under construc-
tion and the ground in the area was
available.
In would have been easy to simply
stop monitoring the inclinometers
when it was determined that the bot-
tom of the casings were not anchored
in stable ground but understanding
their importance and providing the
value added service of providing a
solution is immeasurable to relation-
ships among stakeholders.
Marcelo Chuaqui
General Manager
Wing Lam
Instrumentation Specialist
Monir Precision Monitoring Inc.,
2359 Royal Windsor Drive, Unit 25,
Mississauga, ON, CAN, L5J 4S9,
905-822-0090, marcelo@monir.ca,
wing@monir.ca
Some on-line sources of information about
geotechnical instrumentation
John Dunnicliff
Introduction
This article is intended as a reference
document, and includes the following
on-line sources of information about
geotechnical instrumentation:
• The U.K. Institution of Civil
Engineers on-line manual, Manual
of Geotechnical Engineering
(MOGE)
• Websites of manufacturers of geo-
technical instrumentation.
• Linkedin
• Geotechnical Instrumentation News
(GIN)
The article is based on a paper pre-
sented during the Eighth Symposium
on Field Measurements in GeoMe-
chanics (FMGM), held in Berlin,
Germany in September 2011.
The U.K. Institution of Civil
Engineers on-line manual,
Manual of Geotechnical
Engineering (MOGE)
General description of the manual
MOGE consists of nearly 100 chap-
ters, covering a wide spectrum of
geotechnical engineering: www.icev-
irtuallibrary.com/icemanuals/MOGE.
There are two chapters about geotech-
nical instrumentation and monitoring,
which update parts of the red book:
• Chapter 94. Principles of geotech-
nical monitoring. There are three
sections:
à
à
Benefits of geotechnical moni-
toring
. The principal technical
reasons for recommending
a geotechnical monitoring
program for a project are de-
scribed. A common feature of
these technical reasons is that
monitoring programs generally
save money. Allen Marr is the
author of this section.
à
à
Systematic approach to plan-
ning monitoring programs us-
ing geotechnical instrumenta-
tion.
This 20-step sermon will
be familiar to many readers of
GIN. It includes the vital topic
of how to assign tasks for the
construction phase such that
high quality data are obtained.
The sermon is followed by an
example of planning a moni-
toring program for an embank-
ment on soft ground.
à
à
General guidelines on execu-
tion of monitoring programs
,
including all tasks during the
construction phase.