Geotechnical investigation and testing - Geotechnical monitoring by field instrumentation - Part 1: General rules (ISO 18674-1:2015)

This Standard applies to performance monitoring of the ground, structures interacting with the ground and geotechnical works.
Specifically, this Standard is applicable to field instrumentation and measurements carried out in connection with site investigations of soils and rocks in accordance with EN 1997-2; in connection with the Observational Design procedure in accordance with EN 1997-1; for ground behaviour evaluation, e.g. unstable slopes, consolidation etc or the proof or follow-up of a new equilibrium within the ground, after disturbance of its natural state by construction measures (e.g. foundation loads, excavation of soil, tunnelling); for the proof or follow-up of the stability, serviceability and safety of structures which may be influenced by geotechnical construction; for perpetuation of evidence; for the evaluation and control of geotechnical work.

Geotechnische Erkundung und Untersuchung - Geotechnische Messungen - Teil 1: Allgemeine Regeln (ISO 18674-1:2015)

Die vorliegende Norm gilt für die Leistungsüberwachung von Baugrund, Bauwerken, die mit dem Baugrund in Wechselwirkung stehen, und geotechnische Anlagen.
Im Besonderen gilt diese Norm für die Geräteausrüstung für Feldmessungen (Feldinstrumentation) und Messungen, die durchgeführt werden
   in Verbindung mit Standorterkundungen von Böden und Fels nach EN 1997 2;
   in Verbindung mit der Beobachtungsmethode bei der Planung nach EN 1997 1;
   zur Bewertung des Verhaltens des Baugrunds, z. B. instabile Böschungen, Konsolidation usw.;
   zum Nachweis oder zur Folgeprüfung eines neuen Gleichgewichts im Baugrund nach einer Störung des natürlichen Zustands durch Baumaßnahmen (z. B. Fundamentlasten, Bodenaushub, Tunnelbau);
   zum Nachweis oder Folgeprüfung der Stabilität (Standsicherheit), Gebrauchstauglichkeit und Sicherheit von baulichen Anlagen, die möglicherweise durch geotechnische Anlagen beeinflusst werden;
   zur Beweissicherung;
   zur Bewertung und Lenkung geotechnischer Arbeiten.

Reconnaissance et essais géotechniques - Surveillance géotechnique par instrumentation in situ - Partie 1: Règles générales (ISO 18674-1:2015)

L'ISO 18674-1:2015 établit les règles générales d'exécution de la surveillance du sol, des structures interagissant avec le sol, des remblais géotechniques et des travaux géotechniques.
Elle s'applique spécifiquement à l'instrumentation déployée sur le terrain et aux mesurages réalisés : dans le cadre d'investigations in situ sur des sols et des roches; dans le cadre de la méthode observationnelle; dans le cadre de la performance des structures avant, pendant et après construction; pour l'évaluation du comportement des terrains, par exemple les pentes instables, les phénomènes de consolidation, etc.; pour la preuve ou le suivi d'un nouvel équilibre dans le terrain, après une perturbation de son état naturel par des mesures de construction (par exemple charges dues aux fondations, excavation de sol, creusement de tunnels); pour la preuve ou le suivi de la stabilité, de l'aptitude au service et de la sécurité des structures pouvant être influencées par les travaux géotechniques; pour la perpétuation des preuves; et pour l'évaluation et le contrôle des travaux géotechniques.

Geotehnično preiskovanje in preskušanje - Geotehnične meritve - 1. del: Splošna pravila (ISO 18674-1:2015)

Ta standard velja za meritve tal, struktur v povezavi s tlemi in geotehnična dela. Ta standard še zlasti velja za terenske instrumente in meritve v povezavi s preiskovanjem zemljin in kamnin v skladu s standardom EN 1997-2 v povezavi s postopkom opazovalnega projektiranja (Observational Design) v skladu s standardom EN 1997-1: za oceno vedenja tal, npr. nestabilnih pobočij, konsolidacijo itd. ali dokaz ali spremljanje novega ravnotežja tal po motnjah njihovega naravnega stanja z gradbenimi ukrepi (npr. obremenitve zaradi temeljenja, izkopa zemlje, gradnje predora); za dokaz ali spremljanje stabilnosti, uporabnosti in varnosti struktur, na katere lahko vplivajo geotehnične strukture; za ohranjanje dokazov; za ovrednotenje in nadzor geotehničnih del.

General Information

Status
Published
Public Enquiry End Date
30-Dec-2013
Publication Date
18-Aug-2015
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
10-Jul-2015
Due Date
14-Sep-2015
Completion Date
19-Aug-2015

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SLOVENSKI STANDARD
SIST EN ISO 18674-1:2015
01-september-2015
*HRWHKQLþQRSUHLVNRYDQMHLQSUHVNXãDQMH*HRWHKQLþQHPHULWYHGHO6SORãQD
SUDYLOD ,62
Geotechnical investigation and testing - Geotechnical monitoring by field instrumentation
- Part 1: General rules (ISO 18674-1:2015)
Geotechnische Erkundung und Untersuchung - Geotechnische Messungen - Teil 1:
Allgemeine Regeln (ISO 18674-1:2015)
Reconnaissance et essais géotechniques - Surveillance géotechnique par
instrumentation in situ - Partie 1: Règles générales (ISO 18674-1:2015)
Ta slovenski standard je istoveten z: EN ISO 18674-1:2015
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
SIST EN ISO 18674-1:2015 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 18674-1:2015

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SIST EN ISO 18674-1:2015

EUROPEAN STANDARD
EN ISO 18674-1

NORME EUROPÉENNE

EUROPÄISCHE NORM
May 2015
ICS 13.080.20; 93.020
English Version
Geotechnical investigation and testing - Geotechnical monitoring
by field instrumentation - Part 1: General rules (ISO 18674-
1:2015)
Reconnaissance et essais géotechniques - Surveillance Geotechnische Erkundung und Untersuchung -
géotechnique par instrumentation in situ - Partie 1: Règles Geotechnische Messungen - Teil 1: Allgemeine Regeln
générales (ISO 18674-1:2015) (ISO 18674-1:2015)
This European Standard was approved by CEN on 30 April 2015.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18674-1:2015 E
worldwide for CEN national Members.

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SIST EN ISO 18674-1:2015
EN ISO 18674-1:2015 (E)
Contents Page
Foreword .3
2

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SIST EN ISO 18674-1:2015
EN ISO 18674-1:2015 (E)
Foreword
This document (EN ISO 18674-1:2015) has been prepared by Technical Committee ISO/TC 182
"Geotechnics" in collaboration with Technical Committee CEN/TC 341 “Geotechnical Investigation and
Testing” the secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by November 2015, and conflicting national standards shall be withdrawn
at the latest by November 2015.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 18674-1:2015 has been approved by CEN as EN ISO 18674-1:2015 without any modification.

3

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SIST EN ISO 18674-1:2015

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SIST EN ISO 18674-1:2015
INTERNATIONAL ISO
STANDARD 18674-1
First edition
2015-05-15
Geotechnical investigation and
testing — Geotechnical monitoring by
field instrumentation —
Part 1:
General rules
Reconnaissance et essais géotechniques — Surveillance géotechnique
par instrumentation in situ —
Partie 1: Règles générales
Reference number
ISO 18674-1:2015(E)
©
ISO 2015

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2015 – All rights reserved

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and symbols . 2
3.1 Terms . 2
3.2 Symbols . 4
4 Principal requirements . 5
4.1 Geotechnical monitoring in connection with geotechnical design . 5
4.2 Geotechnical monitoring in connection with specific questions . 5
4.3 Requirements of a geotechnical monitoring project . 5
4.4 Geodetic measurements . 6
4.5 Safety requirements . 6
5 Requirements of a geotechnical monitoring system . 6
5.1 General . 6
5.2 Robustness . 7
5.3 Influencing factors . 7
5.4 Redundancy . 7
5.5 Stability of sensor signal . 7
5.6 Function check and calibration . 8
6 Location of measuring points and geotechnical parameters . 8
6.1 Location of measuring points . 8
6.1.1 The measuring points can be located at free surfaces, at the interface
between any two media, or inside of a medium. . 8
6.2 Measurement and monitoring of geotechnical parameters . 8
7 Carrying out the measurements . 9
8 Data processing and verification . 9
9 Reporting .10
9.1 Installation report .10
9.2 Monitoring report .11
Annex A (normative) Minimum requirements on content of instrument data sheets .13
Annex B (normative) Geotechnical measurements in boreholes .14
Annex C (informative) Field measurements in connection with the design and construction
of geotechnical structures .17
Annex D (informative) Measurement and monitoring of geotechnical key parameters .19
Annex E (informative) Types of instruments and monitoring methods commonly used.21
Bibliography .27
© ISO 2015 – All rights reserved iii

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any
patent rights identified during the development of the document will be in the Introduction and/or on
the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
ISO 18674-1 was prepared by European Committee for Standardization (CEN) in collaboration with
ISO/TC 182, Geotechnics, Subcommittee SC 01, Geotechnical investigation and testing, in accordance with
the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
ISO 18674 consists of the following parts, under the general title Geotechnical investigation and testing
— Geotechnical monitoring by field instrumentation:
— Part 1: General rules
The following parts are under preparation:
— Part 2: Displacement measurements along a line: Extensometers
The following parts are planned:
— Part 3: Displacement measurements across a line: Inclinometers
— Part 4: Piezometers
— Part 5: Total pressure cells
— Part 6: Hydraulic settlement gauges
— Part 7: Strain gauges
— Part 8: Load cells
— Part 9: Geodetic monitoring instruments
— Part 10: Vibration monitoring instruments

NOTE For further information on geotechnical monitoring by field instrumentation, see References [1] to [7].
iv © ISO 2015 – All rights reserved

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SIST EN ISO 18674-1:2015
INTERNATIONAL STANDARD ISO 18674-1:2015(E)
Geotechnical investigation and testing — Geotechnical
monitoring by field instrumentation —
Part 1:
General rules
1 Scope
This part of ISO 18674 lays out the general rules for the performance monitoring of the ground, of
structures interacting with the ground, of geotechnical fills, and of geotechnical works.
NOTE ISO 18674 fulfils the requirements for general rules for the performance monitoring of the ground, of
structures interacting with the ground, of geotechnical fills, and of geotechnical works as part of the geotechnical
[8] [9]
investigation and testing according to EN 1997-1 and EN 1997-2 .
Specifically, this part of ISO 18674 applies to field instrumentation and measurements carried out
— in connection with site investigations of soils and rocks,
— in connection with Observational Design procedures,
— in connection with the performance of geotechnical structures before, during, and after construction,
— for ground behaviour evaluation, e.g. unstable slopes, consolidation etc.,
— for the proof or follow-up of a new equilibrium within the ground, after disturbance of its natural
state by construction measures (e.g. foundation loads, excavation of soil, tunnelling),
— for the proof or follow-up of the stability, serviceability, and safety of structures and operations
which might be influenced by geotechnical construction,
— for perpetuation of evidence, and
— for the evaluation and control of geotechnical works.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 14688-1, Geotechnical investigation and testing — Identification and classification of soil — Part 1:
Identification and description
ISO 14689-1, Geotechnical investigation and testing — Identification and classification of rock — Part 1:
Identification and description
ISO 22475-1, Geotechnical investigation and testing — Sampling methods and groundwater measurements —
Part 1: Technical principles for execution
ISO/IEC Guide 99:2007, International vocabulary of metrology — Basic and general concepts and
associated terms (VIM)
IEC 60529, Degrees of protection provided by enclosures (IP Code)
© ISO 2015 – All rights reserved 1

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

3 Terms and symbols
3.1 Terms
For the purposes of this document, the terms and definitions given in ISO/IEC Guide 99:2007 and the
following apply.
3.1.1
geotechnical monitoring
observation of the ground behaviour and/or performance of geotechnical structures before, during,
and/or after construction
Note 1 to entry: Geotechnical monitoring is an integral part of the Observational Design procedure (see
EN 1997–1: 2004).
Note 2 to entry: Geotechnical monitoring is based on field observation, including construction site inspection.
3.1.2
field instrument
measuring tool to assist geotechnical monitoring
Note 1 to entry: Monitoring by field instruments comprises the measurement of physical parameters, in particular,
the change of the parameter values.
3.1.3
geotechnical key parameter
physical parameter indicative of the geotechnical issue under consideration and subject to
geotechnical monitoring
EXAMPLE Displacement (absolute or relative), strain, inclination, stress, pore pressure, earth pressure,
force, velocity, acceleration, temperature.
3.1.4
geotechnical monitoring project
entirety of aspects and processes which, in a specific project, are relevant for geotechnical monitoring
Note 1 to entry: Includes planning, risk assessment, specifying, procurement, delivery, and installation of a
project-specific monitoring system and collecting, processing, evaluating, and reporting of the monitoring data.
3.1.5
geotechnical monitoring concept
preliminary plan for the measurement of geotechnical key parameters developed within the conceptual
design phase, identifying specific objectives such as risk mitigation to be addressed by monitoring, thereby
considering type of measurement, measuring locations, and schedule(s) for carrying out the measurement
3.1.6
geotechnical monitoring plan
advancement of the monitoring concept within the specification design phase
3.1.7
geotechnical monitoring system
hardware and software to provide field data
Note 1 to entry: Includes instruments signal, transmission (e.g. electric cables), data acquisition, and auxiliary units.
Note 2 to entry: The performance (e.g. the accuracy, stability, precision) of the geotechnical monitoring system
will not necessarily be identical to the performances of the system components.
3.1.8
geotechnical monitoring programme
entirety of those components of a monitoring project which can be systematically planned, consisting of
a monitoring plan and monitoring system
2 © ISO 2015 – All rights reserved

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

3.1.9
commissioning
demonstration and acceptance of the correct functioning of an installed monitoring system
Note 1 to entry: The commissioning criteria are commonly defined in the monitoring plan.
3.1.10
instrument data sheet
manufacturer’s document containing instrument technical specifications
3.1.11
initial measurement
first measurement after installation (see Figure 1)
3.1.12
zero measurement
measurement carried out after stabilization of installation effects (see Figure 1)
Note 1 to entry: The zero measurement is often taken as reference for subsequent measurements, as it is commonly
related to local space and time coordinates.
Note 2 to entry: The zero measurement is commonly carried out with increased measuring effort, e.g. repetition
of measurements, to provide a reliable datum for subsequent measurements.
Y
3
2
1
X
45 67
Key
1 initial measurement
2 zero measurement
3 reference measurement
4 installation period
5 stabilization period
6 period of baseline measurements
7 construction period
X time
Y reading
Figure 1 — Definition of distinct measuring points during a geotechnical monitoring project in
the period up to and including the construction phase
3.1.13
baseline measurements
measurements carried out, subsequent to the zero measurement, over a period of time before any
construction starts, to help in the definition of changes that occur from causes other than construction
EXAMPLE Seasonal changes in groundwater levels, tidal and moisture content changes, climatic changes
such as temperature, and incidence of sunlight.
© ISO 2015 – All rights reserved 3

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

3.1.14
reference measurement
measurement which serves as reference base for previous and subsequent measurements
Note 1 to entry: The reference measurement is also known as datum measurement.
Note 2 to entry: A new reference measurement is often used for a new construction phase.
Note 3 to entry: The reference measurement is often derived from several measurements.
3.1.15
value change measurement
difference between a measurement and the reference measurement
3.1.16
point measurement
measurement of a physical parameter at a point
EXAMPLE Displacement of a measuring point; force of an anchor at its head; stress state in the ground;
porewater pressure in an embankment; water discharge rate at the downstream toe of a dam.
3.1.17
line measurement
measurement of a physical parameter along a line
EXAMPLE Inclinometer measuring survey of a borehole.
3.2 Symbols
For the purpose of this document, the symbols of Table 1 apply.
Table 1 — Symbols
Symbol Name Unit
d borehole diameter m
i number of measurement, measurement direction, or measuring point -
l distance m
u, v, w displacement component in x-, y-, z- direction, respectively m
u porewater pressure Pa
x, y, z local coordinates m
z piezometric level m
w
α angle, inclination Degree or mm/m
ε strain normal to measuring plane -
n
ε ε ε normal strain with reference to borehole coordinates -
x y z
γ γ γ shear strain with reference to borehole coordinates -
xy yz zx
σ σ σ principal stress Pa
1 2 3
σ normal stress with reference to measuring plane Pa
n
σ σ σ normal stress components with reference to borehole coordinates Pa
x y z
τ τ τ shear stress components with reference to borehole coordinates Pa
xy yz zx
NOTE Symbols with more than one meaning (e.g. u) are distinguishable in the context of their use.
4 © ISO 2015 – All rights reserved

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

4 Principal requirements
4.1 Geotechnical monitoring in connection with geotechnical design
Geotechnical monitoring shall be designed, implemented, and evaluated in connection with the
geotechnical design.
NOTE Figure C.1 shows the position of geotechnical monitoring in connection with the design and the
construction of geotechnical structures; see also “observational method” in EN 1997–1: 2004, 2.7.
4.2 Geotechnical monitoring in connection with specific questions
Each geotechnical monitoring project shall be based on at least one specific question that is to be
answered. The question shall be formulated at the start of the monitoring project and actualized
throughout the project with the aid of information from the measurements.
NOTE Monitoring of construction procedures and long-term monitoring of existing safety-sensitive
structures are included.
4.3 Requirements of a geotechnical monitoring project
4.3.1 In a geotechnical monitoring project, all items as defined in 3.1.4 shall be considered in the
sequence described in 4.3.2 to 4.3.7.
4.3.2 Within the initiation and preliminary design phase, reference shall be made to the geotechnical
issue to be addressed. The key parameters shall be identified and their expected range estimated. The
accuracy and the uncertainty with which the key parameters are to be measured and their geotechnically
tolerable limits shall be specified.
4.3.3 Within the conceptual design phase, a concept shall be developed on how to measure the key
parameters of the geotechnical issue under consideration.
NOTE Aspects for consideration are the principal type of the instruments, frequency of measurements,
redundancy in the system, the anticipated operation time of the monitoring system, and potential risks associated
with monitoring.
4.3.4 Within the specification design phase, the monitoring concept shall be refined and transferred
into a comprehensive monitoring programme. Aspects which shall be considered are the instrument
selection based on instrument data sheets (Annex A) together with expected field performance and the
specification of the instrument installation procedure.
NOTE 1 The monitoring plan includes the specification of the measuring procedure, the location of the
monitoring points, the monitoring schedule, and the type of data collection (manual reading or data logging with
or without remote data access).
NOTE 2 The measuring procedure might encompass the measuring principle (physical base of the measurement,
e.g. vibrating wire principle) and of the measuring method (e.g. compensation method, digital/analogue method).
NOTE 3 Field instruments comprise a large variety of sensors with different measuring principles which all
have their specific advantages and disadvantages depending on the type of application. Examples of sensors with
different measuring principles are vibrating wire, current-loop, inductive, capacitive, resistance strain gauge, and
fibre-optical sensors.
4.3.5 Within the installation and data collection phases, it shall be ensured that
— the instrument system is installed as early as possible prior to construction for baseline
measurements (see Figure 1),
— the installation is carried out in such a way as to achieve good conformance of the measuring instruments,
© ISO 2015 – All rights reserved 5

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SIST EN ISO 18674-1:2015
ISO 18674-1:2015(E)

NOTE Good conformance is associated with only insignificant, if any, alterations of the measured values by
the presence of the instrument
— the instruments are operated and handled in accordance with the manufacturer’s instructions, and
— the monitoring system is routinely inspected and adequately protected from site works.
4.3.6 Within the data processing, evaluation, and reporting phase, attention shall be paid to the fact
that the monitoring data are often affected by instrument, installation, and environmental effects (see
5.3). In the evaluation process, plausibility checks of the monitoring data shall be carried out. Checking
shall include instrument, as well as geotechnical aspects (see 8.5).
4.3.7 The monitoring results shall be evaluated in respect to the geotechnical issue under consideration.
4.4 Geodetic measurements
For the support, evaluation, and control of geotechnical measurements, reference shall be made to
geodetic measurements if applicable.
NOTE 1 See ISO 18674-9.
NOTE 2 For comparison of geotechnical and geodetic measurements, see Table C.1.
4.5 Safety requirements
National and site safety regulations shall be followed.
EXAMPLES Regulations for:
— personal health and safety equipment;
— clean air if working in confined spaces;
— ensuring the safety of the measuring system and its components.
5 Requirements of a geotechnical monitoring system
5.1 General
5.1.1 Geotechnical monitoring systems are subject to specific conditions, which shall be accounted for in
the monitoring programme and evaluation of the monitoring data. These conditions include the following:
— mechanical, hydro-mechanical, or thermo-mechanical interaction between critical components of
the geotechnical measuring system (e.g. sensors, measuring lines) and the surrounding medium in
which the components are embedded;
— environmental conditions (e.g. aggressive groundwater and gases; high ground pressure; electro-
magnetic disturbance) which might affect the embedd
...

SLOVENSKI STANDARD
oSIST prEN ISO 18674:2013
01-december-2013
*HRWHKQLþQRSUHLVNRYDQMHLQSUHVNXãDQMH*HRWHKQLþQHPHULWYH6SORãQDSUDYLOD
,62',6
Geotechnical investigation and testing - Geotechnical monitoring by field instrumentation
- General rules (ISO/DIS 18674:2013)
Geotechnische Erkundung und Untersuchung - Geotechnische Messungen - Allgemeine
Regeln (ISO/DIS 18674:2013)
Reconnaissance et essais géotechniques - Mesures géotechniques - Principes (ISO/DIS
18674:2013)
Ta slovenski standard je istoveten z: prEN ISO 18674
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
oSIST prEN ISO 18674:2013 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 18674:2013

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oSIST prEN ISO 18674:2013
DRAFT INTERNATIONAL STANDARD
ISO/DIS 18674
ISO/TC 182/SC 1 Secretariat: DIN
Voting begins on: Voting terminates on:
2013-08-08 2014-01-08
Geotechnical investigation and testing — Geotechnical
monitoring by field instrumentation — General rules
Reconnaissance et essais géotechniques — Mesures géotechniques — Principes
ICS: 13.080.20;93.020
ISO/CEN PARALLEL PROCESSING
This draft has been developed within the European Committee for Standardization
(CEN), and processed under the CEN lead mode of collaboration as defined in the
Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member
bodies for a parallel five month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments
received, will be submitted to a parallel two-month approval vote in ISO and
THIS DOCUMENT IS A DRAFT CIRCULATED
formal vote in CEN.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
To expedite distribution, this document is circulated as received from the
IN ADDITION TO THEIR EVALUATION AS
committee secretariat. ISO Central Secretariat work of editing and text
BEING ACCEPTABLE FOR INDUSTRIAL,
composition will be undertaken at publication stage.
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USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 18674:2013(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2013

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Copyright notice
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ii © ISO 2013 – All rights reserved

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oSIST prEN ISO 18674:2013
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Contents Page
Foreword . 4
1 Scope . 4
2 Normative references . 4
3 Terms and symbols . 5
3.1 Terms . 5
3.2 Symbols . 8
4 Principal requirements . 8
4.1 Geotechnical monitoring in connection with geotechnical design . 8
4.2 Geotechnical monitoring in connection with specific question(s) . 8
4.3 Requirements on a geotechnical monitoring project . 9
4.4 Geodetic measurements . 10
4.5 Safety requirements . 10
5 Requirements on a geotechnical monitoring system . 11
5.1 General . 11
5.2 Robustness . 11
5.3 Influencing factors . 11
5.4 Redundancy . 12
5.5 Stability of sensor signal . 12
5.6 Function check and calibration . 12
6 Location of measuring points and geotechnical parameters . 12
6.1 Location of measuring points . 12
6.2 Measurement and monitoring of geotechnical parameters . 13
7 Carrying out of the measurements . 13
8 Data processing and verification . 14
9 Reporting . 15
9.1 Installation report . 15
9.2 Monitoring report . 15
Annex A (normative) . 17
Minimum requirements on content of instrument data sheets . 17
Geotechnical measurements in boreholes . 18
Annex C (informative) . 20
Field measurements in connection with the design and construction of geotechnical structures . 20
Annex D (informative) . 22
Measurement and monitoring of geotechnical parameters . 22
D.1 Geotechnical parameters and their measurement . 22
D.2 Monitoring of geotechnical parameters (value change measurements) . 23
Annex E (informative) . 24
Types of instruments and monitoring methods commonly used in geo-engineering (after [3]) . 24
Bibliography . 31

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Foreword
1 Scope
This Standard applies to performance monitoring of the ground, structures interacting with the ground and
geotechnical works.
Specifically, this Standard applies to field instrumentation and measurements carried out
⎯ in connection with site investigations of soils and rocks in accordance with EN 1997-2;
⎯ in connection with the Observational Design procedure in accordance with EN 1997-1;
⎯ for ground behaviour evaluation, e.g. unstable slopes, consolidation etc.
⎯ for the proof or follow-up of a new equilibrium within the ground, after disturbance of its natural state by
construction measures (e.g. foundation loads, excavation of soil, tunnelling);
⎯ for the proof or follow-up of the stability, serviceability and safety of structures which may be influenced by
geotechnical construction;
⎯ for perpetuation of evidence;
⎯ for the evaluation and control of geotechnical works.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 14688-1, Geotechnical investigation and testing – Identification and classification of soil – Part 1:
Identification and description
ISO 14689-1, Geotechnical investigation and testing – Identification and classification of rock – Part 1:
Identification and description
ISO 22475-1, Geotechnical investigation and testing – Sampling by drilling and excavation methods and
groundwater measurements – Part 1: Technical principles for execution
ISO/IEC Guide 99:2007, International vocabulary of metrology – Basic and general concepts and associated
terms (VIM)
EN 1997-1, Eurocode 7, Geotechnical design – General rules
EN 1997-2, Eurocode 7, Geotechnical design – Ground investigation and testing
Geotechnical investigation and testing – Geotechnical monitoring by field instrumentation – Part 2:
Displacement measurements along a line: Extensometers
Geotechnical investigation and testing – Geotechnical monitoring by field instrumentation – Part 3:
Displacement measurements across a line: Inclinometers and deflectometers
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NOTE Further parts on total pressure cells, piezometers, hydraulic settlement gauges, strain gauges, load cells,
geodetic monitoring instruments and vibration monitoring instruments are in preparation.
3 Terms and symbols
3.1 Terms
For the purpose of this document the terms and definitions of ISO/IEC Guide 99:2007 apply as well as the
following terms and definitions:
3.1.1
geotechnical monitoring
observation of the ground behaviour and/or performance of geotechnical structures before, during and/or after
construction.
NOTE 1 Geotechnical monitoring is an integral part of the Observational Design procedure (see EN 1997-1: 2004).
NOTE 2 Geotechnical monitoring is based on field observation, including construction site inspection.
3.1.2
field instrument
measuring tool to assist field observation
NOTE Monitoring by field instruments comprises the measurement of physical parameters, in particular the change of
the parameter values.
3.1.3
geotechnical key parameter
physical parameter indicative of the geotechnical problem under consideration and subject to geotechnical
monitoring
EXAMPLES Displacement (absolute or relative), settlement, heave, strain, inclination, stress, pore pressure, earth
pressure, force, temperature.
3.1.4
geotechnical monitoring project
entirety of aspects and processes which, in a specific project, are relevant for geotechnical monitoring. It
includes planning, specifying, procurement, delivery and installation of a project-specific monitoring system
and collecting, processing and evaluating of the monitoring data
3.1.5
geotechnical monitoring concept
preliminary plan for the measurement of geotechnical key parameters within the conceptual design phase,
considering type of measurement, measuring locations and schedule of carrying out the measurements
3.1.6
geotechnical monitoring plan
advancement of the monitoring concept within the specification design phase
3.1.7
geotechnical monitoring programme
entirety of those components of a monitoring project which can be systematically planned, consisting of
monitoring plan and monitoring system
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3.1.8
geotechnical monitoring system
hardware and software to provide field data. It includes instruments, signal transmission (e.g. electric cables),
data acquisition and auxiliary units.
3.1.9
commissioning
demonstration and acceptance of the correct functioning of an installed monitoring system
NOTE The commissioning criteria should be defined in the monitoring programme
3.1.10
instrument data sheet
manufacturer’s document containing instrument technical specifications
3.1.11
initial measurement
first measurement after installation (see Figure 1)



3

2







• •

• • •

• • •






1








Time
4 5 6 7


Legend

1 initial measurement
2 zero measurement

3 reference measurement
4 installation period

5 stabilisation period

6 period of baseline measurements
7 construction period

Figure 1 – Definition of distinct measuring points in the initial phase of a geotechnical monitoring
project

3.1.12
zero measurement
measurement carried out after stabilisation of installation effects (see Figure 1)
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NOTE 1 The zero measurement is often taken as reference for subsequent measurements, as it is commonly related
to local space and time co-ordinates.
NOTE 2 The zero measurement is commonly carried out with increased measuring effort, e.g. repetition of
measurements, to provide a reliable datum for subsequent measurements.
3.1.13
baseline measurements
measurements carried out, subsequent to the zero measurement, over a period of time before any con-
struction starts, to help in the definition of changes that occur from causes other than construction.
EXAMPLES Seasonal changes in groundwater levels, tidal and moisture content changes, climatic changes such as
temperature and incidence of sunlight
3.1.14
reference measurement
measurement which serves as reference base for previous and subsequent measurements
NOTE 1 The reference measurement is also known as datum measurement.
NOTE 2 A new reference measurement is often used for a new construction phase
NOTE 3 The reference measurement is often derived from several measurements
3.1.15
value change measurement
difference between a measurement and the reference measurement
3.1.16
point measurement
measurement of a physical parameter at a point
EXAMPLES Displacement of a measuring point; force of an anchor at its head; stress state in the ground; porewater
pressure in an embankment; water discharge rate at the downstream toe of a dam.
3.1.17
line measurement
measurement of a physical parameter along a line
EXAMPLE Inclinometer measuring survey of a borehole
NOTE The measurement of the distance between two measuring points, for example the convergence measurement
in tunnelling, is a special case of a line measurement.

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3.2 Symbols
For the purpose of this document, the symbols of Table 1 apply.
Table 1 — Symbols

Symbol Name Unit
d borehole diameter m
i number of measurement, measurement direction or measuring point -
distance m
l
u, v, w displacement component in x-, y-, z- direction, respectively m
u porewater pressure Pa
x, y, z
local co-ordinates m
z piezometric level  m
w
α angle, inclination Degree or mm/m
ε strain normal to measuring plane -
n
ε ε ε normal strain with reference to borehole co-ordinates -
x y z
shear strain with reference to borehole co-ordinates Degree
γ γ γ
xy yz zx
σ σ σ principal stress Pa
1 2 3
σ normal stress with reference to measuring plane Pa
n
normal stress components with reference to borehole co-ordinates Pa
σ σ σ
x y z
τ τ τ shear stress components with reference to borehole co-ordinates Pa
xy yz zx

NOTE Symbols with more than one meaning (e.g. i, u) are distinguishable on the basis of their use

4 Principal requirements
4.1 Geotechnical monitoring in connection with geotechnical design
Geotechnical monitoring shall be designed, implemented and evaluated in connection with the geotechnical
design.
NOTE Figure C.1 in Annex C shows the position of geotechnical monitoring in connection with the design and the
construction of geotechnical structures; see also “observational method” in EN 1997-1: 2004, Sections 2.7 and 4.5
4.2 Geotechnical monitoring in connection with specific question(s)
Each geotechnical monitoring project shall be based on at least one specific question that is to be answered.
The question shall be formulated at the start of the monitoring project and actualised throughout the project
with the aid of information from the measurements.
NOTE It is implied that monitoring of construction procedures and long-term monitoring of existing safety-sensitive
structures are included.
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4.3 Requirements on a geotechnical monitoring project
4.3.1 In a geotechnical monitoring project, all items and courses of action, as depicted in Figure 2, shall be
considered.


Initiation and
Geotechnical problem identification
preliminary Objective of monitoring project

design phase Key parameter identification

Conceptual
Monitoring concept
design phase


Specification Monitoring programme
Monitoring plan and monitoring system
design phase

Instrumentation requirements Location Schedule
plan of for taking
- Sensors (measuring method)

measuring the
- Signal transmission;
points readings
measuring lines

- Data acquisition
Installation requirements and procedures


Installation and
Installation
data collection Carrying out of the measurements

Plausibility check
phase

Data processing,

Monitoring Report
evaluation and
reporting phase


Figure 2 – Topics and course of action of a geotechnical monitoring project

4.3.2 Within the initiation and preliminary design phase, reference shall be made to the geotechnical
problem to be addressed (see EN 1997-1: 2004). The key parameters shall be identified and their expected
range estimated. The accuracy and the uncertainty with which the key parameters are to be measured and
their geotechnically tolerable limits shall be specified.
4.3.3 Within the conceptual design phase, a concept shall be developed on how to measure the key
parameters of the geotechnical problem under consideration.
NOTE Aspects for consideration are the principal type of the instruments, frequency of measurements, redundancy
in the system and the anticipated operation time of the monitoring system.
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4.3.4 Within the specification design phase, the monitoring concept shall be refined and transferred into a
comprehensive monitoring programme. This programme encompasses the monitoring plan and the monitoring
system and, as such, includes all components of a monitoring project which can be planned ahead of the
measurements. Important aspects of this phase are the instrument selection based on instrument data sheets
(Annex A) together with expected field performance and the specification of the instrument installation
procedure.
NOTE 1 The monitoring plan includes the specification of the measuring procedure, the location of the monitoring
points, the monitoring schedule and the type of data collection (manual reading or data logging with or without remote data
access).
NOTE 2 The measuring procedure may encompass the measuring principle (physical base of the measurement; e.g.
vibrating wire principle) and of the measuring method (e. g. compensation method, digital/analogue method).
NOTE 3 Field instruments comprise a large variety of sensors with different measuring principles which all have their
specific advantages and disadvantages depending on the type of application. Examples of sensors with different
measuring principles are vibrating wire, current-loop, inductive, capacitive, resistance strain gauge and fibre-optical
sensors.
4.3.5 Within the installation and data collection phase, it shall be attempted
- to install the instrument system as early as possible prior to construction for baseline measurements (see
Figure 1);
- to carry out the installation in such a way as to achieve good conformance of the measuring instruments;
NOTE Good conformance is associated with only insignificant, if any, alterations of the measured values by the
presence of the instrument
- to operate and handle the instruments in accordance with the manufacturer’s instructions.
NOTE For carrying out of the measurements, see 7.
4.3.6 Within the data processing, evaluation and reporting phase, attention shall be paid to the fact that the
monitoring data are often affected by instrument, installation and environmental effects (see 5.3). In all phases
of the evaluation process, plausibility checks of the monitoring data are essential. Checking shall include
instrument as well as geotechnical aspects (see 8.5).
4.3.7 The monitoring results shall be evaluated in respect to the geotechnical problem under consideration.
4.4 Geodetic measurements
For the support, evaluation and control of geotechnical measurements it is often necessary to refer to geodetic
measurements.
NOTE For comparison of geotechnical and geodetic measurements, see Annex C, Table C.1.
4.5 Safety requirements
National safety regulations shall be followed.
EXAMPLES Regulations for
- personal health- and safety equipment;
- clean air if working in confined spaces;
- ensuring the safety of the measuring system and its components.
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5 Requirements on a geotechnical monitoring system
5.1 General
5.1.1 Geotechnical monitoring systems are subject to specific conditions, which shall be accounted for in
the monitoring programme and evaluation of the monitoring data. These conditions include:
- mechanical, hydro-mechanical or thermo-mechanical interaction between critical components of the
geotechnical measuring system (e.g. sensors, measuring lines) and the surrounding medium in which the
components are embedded;
- environmental conditions (e.g. aggressive groundwater and gases; high ground pressure; electro-
magnetic disturbance) which might affect the embedded components;
- vulnerability of the data communication of the monitoring system (e.g. long measuring lines, often passing
through construction zones).
5.1.2 Requirements 5.2 to 5.6 shall be documented.
NOTE  Manufacturers’ documentation, e.g. instrument data sheets (see Annex A), should provide a basis to make an
informed choice of the instruments.
5.2 Robustness
5.2.1 The components of a geotechnical monitoring system shall be sufficiently robust against harsh
environmental and construction site conditions.
NOTE This requirement relates to the material used (e.g. quality of the measuring cable; corrosion resistance of
sensors), the type of construction of the installed units and to the safety of the entire monitoring system e.g. towards over-
voltage (lightning protection), disturbance from the construction site and vandalism.
5.2.2 Failure in data communication, e.g. of cables, radio links, is a potential problem. When planning
geotechnical monitoring systems these risks should be minimised.
EXAMPLE In automatic monitoring systems provision for communication failure alarms and low power levels.
5.3 Influencing factors
5.3.1 For the evaluation of geotechnical measurements it is essential to address all relevant factors which
influence the sensor signal. Conceptually, discrimination shall be made between direct and indirect influences
onto the measured physical quantity.
NOTE 1 Direct influences are related to the monitoring object, indirect influences to the monitoring system.
NOTE 2 Common factors that can influence the monitoring system are changes of the temperature and atmospheric
pressure.
NOTE 3 The monitoring system may also be influenced by man-made factors such as high voltage lines and electro-
magnetic disturbance.
5.3.2 Provisions shall be made to discriminate between the respective effects of the influencing factors
onto the monitoring object and monitoring system.
EXAMPLES Choice of temperature-compensated displacement transducer; pressure-compensated piezometer;
extensometer rods with a material of low thermal expansion coefficient; temperature correction of convergence tape
measurements (see Part 2).
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5.4 Redundancy
Geotechnical measurements should include redundancy to ensure the functioning of the system despite
possible component malfunction. A redundancy in the measuring data should be used for the identification of
erroneous readings and for data corrections.
EXAMPLES (in order of increasing degree of redundancy):
– multiple readings;
– installation of more sensors than theoretically required, e.g. more than 3 sensors in 2-D stress monitoring;
– duplication of sensors of the same measuring principle;
– application of different measuring principles for one and the same quantity (“diversification”), e.g. control of an
inclinometer survey by geodetic measurements of the head of an inclinometer borehole (see Part 3)
5.5 Stability of sensor signal
As a re-calibration (see 5.6) of permanently embedded sensors is hardly possible, attention shall be given to
the stability of the measuring signal of sensors and to the redundancy of the monitoring system. It should be
ensured that the signal could be expected to be sufficiently stable over the time span of the monitoring project.
NOTE Safety-sensitive geotechnical structures such as tunnels and dams often require long-term monitoring.
5.6 Function check and calibration
Function checks and/or instrument calibrations shall be carried out and documented at the following stages of
the monitoring project:
- Calibrations prior to shipment. These shall be the responsibility of the manufacturer and are to be
documented in calibration certificates.
- Function checks before installation (pre-installation acceptance tests) to verify that no damage has
occurred to the instruments during transit. If applicable, this also includes checking of the zero point and
scale of the system components.
- Function checks after installation of the instrument system (post-installation acceptance tests).
- Calibrations during service life. The accessible components of the monitoring systems shall be re-
calibrated in certain intervals. The interval between any two re-calibrations shall be addressed in the
monitoring programme, considering also the recommendations of the manufacturer. An immediate
calibration must be carried out if reasonable doubts exist on the reliability or accuracy of an instrument
component. Additional re-calibrations may become necessary in specific measuring applications (see
Parts 2 and following).
6 Location of measuring points and geotechnical parameters
6.1 Location of measuring points
6.1.1 The measuring points can be located at free surfaces, at the interface between any two media or
inside of a medium.
6.1.2 Measuring points in the ground are to be installed in boreholes. The measurement of these points
should be related to the local co-or
...

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