SIST EN ISO 22477-4:2018

Geotechnical investigation and testing - Testing of geotechnical structures - Part 4: Testing of piles dynamic load testing (ISO 22477-4:2018)

This standard establishes the specifications for the execution of dynamic pile load tests in which a single pile is subject to an axial short duration impact load in compression to predict its ultimate compressive resistance and load-displacement behaviour including shaft friction distribution and toe resistance.

Geotechnische Erkundung und Untersuchung - Prüfung von geotechnischen Bauwerken und Bauwerksteilen - Teil 4: Pfahlprüfungen: Dynamische Pfahlprobebelastung (ISO 22477-4:2018)

Das vorliegende Dokument legt die Spezifikationen für die Ausführung von dynamischen Probebelastungen, in denen ein einziger Pfahl einer axialen dynamischen Belastung unterliegt, fest.
Dieses Dokument beschreibt die erforderlichen Prüfmethoden für die Beurteilung des Pfahlwiderstands, der mit den folgenden Methoden und Verfahren, beschrieben in EN 1997-1:2004+A1:2013, bestimmt wird:
a) Stoßprüfung – Bestimmung des Pfahldruckwiderstands durch Auswertung der Messungen von Dehnung und Beschleunigung und/oder Verschiebung am Pfahlkopf in Abhängigkeit von der Zeit;
b) Rammformeln – Bewertung des Pfahldruckwiderstands aus Schlagzahl und Energie des Hammers während der Rammarbeiten;
c) Analyse von Wellengleichungen – Bewertung des Pfahldruckwiderstands aus der Schlagzahl durch die Modellierung des Pfahls, des Bodens und des Rammgeräts;
d) dynamische Multischlag-Prüfung – Bewertung des Pfahldruckwiderstands aus einer Serie von Schlägen, die dazu bemessen sind, unterschiedliche Niveaus von Pfahlkopfverschiebung und -geschwindigkeit zu erzeugen.
Dieses Dokument gilt für axialbelastete, druckbeanspruchte Pfähle.
Dieses Dokument gilt für sämtliche in EN 1536, EN 12699 und EN 14199 genannten Pfahlarten.
Die in diesem Dokument berücksichtigten Prüfungen sind ausschließlich auf dynamische Probebelastungen an Pfählen beschränkt.
ANMERKUNG 1 ISO 22477-4 kann in Verbindung mit EN 1997-1:2004+A1:2013 angewendet werden. Numerische Teilsicherheitsbeiwerte für Grenzzustände aus Pfahlprobebelastungen, die bei der Bemessung berücksichtigt werden müssen, werden in EN 1997-1 zur Verfügung gestellt. Für eine Bemessung nach EN 1997-1 werden die Ergebnisse der dynamischen Probebelastungen als äquivalent zur gemessenen Druckfestigkeit Rc,m angesehen, nachdem diese einer geeigneten Analyse unterzogen wurden.
ANMERKUNG 2 Hinweise zu den Analyseverfahren für die Ergebnisse dynamischer Probebelastungen werden in den Anhängen A, B, D, E und F gegeben.
Dieses Dokument bietet Spezifikationen für:
i) Untersuchungsprüfungen, wobei ein Probepfahl bis zum Grenzzustand der Tragfähigkeit belastet wird;
ii) Kontrollprüfungen, wobei der Pfahl mit einer spezifischen Last oberhalb des Grenzzustands der Gebrauchstauglichkeit belastet wird.
ANMERKUNG 3 Im Allgemeinen konzentriert sich eine Untersuchungsprüfung auf die allgemeinen Kenntnisse zu einem Pfahltyp; eine Kontrollprüfung konzentriert sich auf eine bestimmte Pfahlanwendung.

Reconnaissance et essais géotechniques - Essais de structures géotechniques - Partie 4: Essais de pieux: essai de chargement dynamique (ISO 22477-4:2018)

Le présent document établit les spécifications relatives à l'exécution des essais de chargement dynamique au cours desquels un pieu unique est soumis à une charge de compression axiale dynamique.
Il précise les méthodes d'essai nécessaires pour permettre une évaluation de la résistance d'un pieu, déterminée à partir des méthodes et des procédures décrites dans la norme EN1997-1:2004+A1:2013:
a)    Essai d'impact dynamique: détermination de la résistance à la compression d'un pieu par évaluation des mesures de déformation et d'accélération et/ou de déplacement, prises au niveau de la tête du pieu, en fonction du temps.
b)    Formules de fonçage de pieux: évaluation de la résistance à la compression d'un pieu à partir du nombre de coups de battage et de l'énergie du mouton pendant le fonçage du pieu.
c)    Analyse de l'équation d'onde: évaluation de la résistance à la compression d'un pieu à partir du nombre de coups de battage par modélisation du pieu, du sol et de l'équipement de fonçage.
d)    Essais dynamiques basés sur une série de coups ? évaluation de la résistance à la compression d'un pieu à partir d'une série de coups conçue pour créer des niveaux différents de déplacements et de vitesses de tête de pieu.
Ce document s'applique aux pieux sous chargement axial en compression.
Il s'applique à tous les types de pieux mentionnés par l'EN 1536, l'EN 12699 et l'EN 14199.
Les essais envisagés dans le présent document sont limités aux essais de chargement dynamique des pieux uniquement.
NOTE 1    L'ISO 22477-4 peut être utilisée conjointement à l'EN1997-1:2004+A1:2013. Les valeurs numériques des facteurs partiels des états limites, obtenues à partir des essais de chargement des pieux et devant être prises en compte dans la conception, sont données dans l'EN 1997-1. Dans le cas d'une conception selon l'EN 1997-1, les résultats des essais de chargement dynamique seront considérés comme équivalents à la résistance à la compression mesurée Rc,m après l'analyse appropriée.
NOTE 2    Des consignes relatives aux procédures d'analyse des résultats des essais de chargement dynamique sont données dans les Annexes A, B, D, E et F.
Le présent document fournit des spécifications pour:
i)     les essais préalables, au cours desquels un pieu sacrificiel est chargé jusqu'à l'état limite ultime;
ii)    les essais de contrôle, au cours desquels le pieu est chargé jusqu'à une charge spécifiée au-delà de l'état limite de service.
NOTE 3    En général, un essai préalable se focalise sur la connaissance générale d'un type de pieu; un essai de contrôle se focalise sur une application particulière d'un pieu.

Geotehnično preiskovanje in preskušanje - Preskušanje geotehničnih konstrukcij - 4. del: Preskušanje pilotov: dinamični obremenilni preskus (ISO 22477-4:2018)

Ta standard podaja specifikacije za izvedbo dinamičnih obremenilnih preskusov pilotov, pri katerih je en pilot izpostavljen kratkotrajni osni udarni obremenitvi pri stiskanju, da bi se lahko napovedala njegova končna odpornost na stiskanje in vedenje ob premiku bremena, vključno s porazdelitvijo trenja gredi in nožno odpornostjo.

General Information

• Status: Published
• Public Enquiry End Date: 29-Dec-2016
• Publication Date: 16-May-2018
• ICS: 93.020 - Earthworks. Excavations. Foundation construction. Underground works
• Technical Committee: KON.007 - Geotechnics
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 23-Apr-2018
• Due Date: 28-Jun-2018
• Completion Date: 17-May-2018
• Ref Project: EN ISO 22477-4:2018 - Geotechnical investigation and testing - Testing of geotechnical structures - Part 4: Testing of piles: dynamic load testing (ISO 22477-4:2018)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 22477-4:2018
01-junij-2018
*HRWHKQLþQRSUHLVNRYDQMHLQSUHVNXãDQMH3UHVNXãDQMHJHRWHKQLþQLKNRQVWUXNFLM
GHO3UHVNXãDQMHSLORWRYGLQDPLþQLREUHPHQLOQLSUHVNXV,62
Geotechnical investigation and testing - Testing of geotechnical structures - Part 4:
Testing of piles dynamic load testing (ISO 22477-4:2018)
Geotechnische Erkundung und Untersuchung - Prüfung von geotechnischen Bauwerken
und Bauwerksteilen - Teil 4: Pfahlprüfungen: Dynamische Pfahlprobebelastung (ISO
22477-4:2018)
Reconnaissance et essais géotechniques - Essais de structures géotechniques - Partie
4: Essais de pieux: essai de chargement dynamique (ISO 22477-4:2018)
Ta slovenski standard je istoveten z: EN ISO 22477-4:2018
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
SIST EN ISO 22477-4:2018 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 22477-4:2018

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SIST EN ISO 22477-4:2018


EN ISO 22477-4
EUROPEAN STANDARD

NORME EUROPÉENNE

April 2018
EUROPÄISCHE NORM
ICS 93.020
English Version

Geotechnical investigation and testing - Testing of
geotechnical structures - Part 4: Testing of piles: dynamic
load testing (ISO 22477-4:2018)
Reconnaissance et essais géotechniques - Essais de Geotechnische Erkundung und Untersuchung - Prüfung
structures géotechniques - Partie 4: Essais de pieux: von geotechnischen Bauwerken und Bauwerksteilen -
essai de chargement dynamique (ISO 22477-4:2018) Teil 4: Pfahlprüfungen: Dynamische
Pfahlprobebelastung (ISO 22477-4:2018)
This European Standard was approved by CEN on 24 February 2018.

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, Serbia, 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: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 22477-4:2018 E
worldwide for CEN national Members.

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SIST EN ISO 22477-4:2018
EN ISO 22477-4:2018 (E)
Contents Page
European foreword . 3


2

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SIST EN ISO 22477-4:2018
EN ISO 22477-4:2018 (E)
European foreword
This document (EN ISO 22477-4:2018) 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 October 2018, and conflicting national standards shall
be withdrawn at the latest by October 2018.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 22477-4:2018 has been approved by CEN as EN ISO 22477-4:2018 without any
modification.

3

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SIST EN ISO 22477-4:2018

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SIST EN ISO 22477-4:2018
INTERNATIONAL ISO
STANDARD 22477-4
First edition
2018-03
Geotechnical investigation and
testing — Testing of geotechnical
structures —
Part 4:
Testing of piles: dynamic load testing
Reconnaissance et essais géotechniques — Essais de structures
géotechniques —
Partie 4: Essais de pieux: essai de chargement dynamique
Reference number
ISO 22477-4:2018(E)
©
ISO 2018

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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved

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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 2
3 Terms, definitions and symbols . 2
3.1 Terms and definitions . 2
3.2 Symbols . 4
4 Testing equipment . 4
4.1 General . 4
4.2 Loading . 5
4.2.1 General. 5
4.2.2 Loading by an impact driving system . 6
4.2.3 Loading by a single or multiple blow drop mass . 6
4.3 Measurements . 6
4.3.1 General. 6
4.3.2 Measurements for dynamic impact tests . 7
4.3.3 Measurements and recordings required for pile driving formula or wave
equation analysis . 8
5 Test procedure . 9
5.1 Preparation for testing . 9
5.2 Safety requirements . 9
5.2.1 People and equipment in the surrounding area . 9
5.2.2 Test pile .10
5.3 Preparation of the pile .10
5.4 Timing of tests .10
5.4.1 General.10
5.4.2 Driving — Continuous monitoring and end of initial driving test .10
5.4.3 Re-driving .10
5.4.4 Bored or cast-in-situ piles .11
6 Test results .11
6.1 Test results for dynamic load test with driving formula .11
6.2 Test results for dynamic load test with wave equation analysis .11
6.3 Test results for dynamic load test with measurements at the pile head .11
7 Test reporting .12
Annex A (informative) Driving formula .14
Annex B (informative) Wave equation analysis .17
Annex C (informative) Examples of transducer attachment and pile extension details .27
Annex D (informative) Evaluation by closed form solutions using empirical damping values .29
Annex E (informative) Evaluation of the measurements by signal matching .36
Annex F (informative) Multi-blow dynamic testing technique .44
Bibliography .51
© ISO 2018 – All rights reserved iii

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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(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 voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/ iso/ foreword .html.
This document was prepared by the European Committee for Standardization (CEN) Technical
Committee CEN/TC 341, Geotechnical investigation and testing, in collaboration with ISO Technical
Committee TC 182, Geotechnics, in accordance with the Agreement on technical cooperation between
ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 22477 series can be found on the ISO website.
iv © ISO 2018 – All rights reserved

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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

Introduction
This document establishes the specifications for the execution of dynamic load tests in which a single
pile is subject to an axial load in compression to measure strain, acceleration and displacement under
dynamic loading and to allow an assessment of its compressive resistance. This document outlines
how a dynamic load test is defined and specifies the equipment and testing procedures required.
Informative non-prescriptive guidance is included on the analysis of dynamic load test results required
to determine mobilized or ultimate measured compressive resistance of a pile.
© ISO 2018 – All rights reserved v

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SIST EN ISO 22477-4:2018
INTERNATIONAL STANDARD ISO 22477-4:2018(E)
Geotechnical investigation and testing — Testing of
geotechnical structures —
Part 4:
Testing of piles: dynamic load testing
1 Scope
This document establishes the specifications for the execution of dynamic load tests in which a single
pile is subject to an axial dynamic load in compression.
This document outlines the methods of testing required to allow assessment of pile resistance to be
determined from the following methods and procedures described in EN1997 -1: 2004+A1: 2013:
a) dynamic impact testing – determination of pile compressive resistance by evaluation of
measurements of strain and acceleration and or displacement at the pile head with respect to time;
b) pile driving formulae – evaluation of pile compressive resistance from blow counts and hammer
energy during pile driving;
c) wave equation analysis – evaluation of pile compressive resistance from blow counts by modelling
of the pile, soil and driving equipment;
d) multi-blow dynamic testing – evaluation of pile compressive resistance from a series of blows
designed to generate different levels of pile head displacement and velocity.
This document is applicable to piles loaded axially in compression.
This document is applicable to all pile types mentioned in EN 1536, EN 12699 and EN 14199.
The tests considered in this document are limited to dynamic load tests on piles only.
NOTE 1 ISO 22477-4 can be used in conjunction with EN1997 -1: 2004+A1: 2013. Numerical values of partial
factors for limit states from pile load tests to be taken into account in design are provided in EN 1997-1. For design
to EN 1997-1 the results from dynamic load tests will be considered equivalent to the measured compressive
resistance R after being subject to appropriate analysis.
c,m
NOTE 2 Guidance on analysis procedures for dynamic load testing results is given in Annexes A, B, D, E and F.
This document provides specifications for:
i) investigation tests, whereby a sacrificial pile is loaded up to ultimate limit state;
ii) control tests, whereby the pile is loaded up to a specified load in excess of the serviceability
limit state.
NOTE 3 Generally, an investigation test focuses on general knowledge of a pile type; a control test focuses on
one specific application of a pile.
© ISO 2018 – All rights reserved 1

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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
EN1997 -1: 2004+A1: 2013, Eurocode 7: Geotechnical design — Part 1: General rules
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions in EN1997 -1: 2004+A1: 2013 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1.1
trial pile
pile installed before the commencement of the main piling works or a specific part of the works for
the purpose of investigating the suitability of the chosen type of pile and for confirming its design,
dimensions and compressive resistance
Note 1 to entry: The trial pile might be sacrificed to achieve ultimate limit state.
3.1.2
working pile
pile that will form part of the foundation of the structure
3.1.3
test pile
pile to which loads are applied to determine the compressive resistance - deformation characteristics
of the pile and the surrounding ground
Note 1 to entry: A test pile can be a trial pile or a working pile.
3.1.4
pile load
axial compressive load (or force) applied to the head of the pile during the test
3.1.5
dynamic load
axial compressive impact load (or force) applied to the head of a pile by a driving hammer or drop mass
3.1.6
maximum pile load
highest axial compressive force applied to the pile during the test
Note 1 to entry: This is generally defined prior to the test.
3.1.7
dynamic load test
test where a pile is subjected to chosen axial dynamic load at the pile head to allow the determination of
its compressive resistance
2 © ISO 2018 – All rights reserved

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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

3.1.8
dynamic impact test
pile test with measurement of strain, acceleration and displacement versus time during the impact event
Note 1 to entry: The impact event is normally a hammer blow.
Note 2 to entry: This test is used to assess the compressive resistance of individual piles.
3.1.9
driving formula
formula that relates impact hammer energy and number of blows for a unit distance or permanent set
for a single blow to pile compressive resistance
3.1.10
wave equation analysis
analysis of a dynamically loaded pile by a mathematical model that can represent the dynamic behaviour
of the pile by the progression of stress waves in the pile and the resulting response of the soil
3.1.11
signal matching
operation to evaluate the shaft and base resistance of piles by modelling of the pile and soil with
variation of parameters to match measured signals from pile head strain or displacement and
acceleration measurements
3.1.12
impedance
the dynamic stiffness of a pile determined from the cross-sectional area, material stiffness and density.
Note 1 to entry: For a non-uniform pile the impedance can be different over the length of the pile.
3.1.13
mobilized compressive resistance
the resistance that is mobilized with the available energy of the impact device
3.1.14
ultimate measured compressive resistance
corresponding state in which the pile foundation displaces significantly with negligible increase of
resistance
Note 1 to entry: Where it is difficult to define an ultimate limit state from a load settlement plot showing a
continuous slight increase, a settlement of the pile top equal to 10 % of the pile base diameter should be adopted
as the “failure” criterion.
Note 2 to entry: The ultimate compressive resistance is not measured directly during a dynamic load test. The
measured or mobilized compressive resistance obtained from dynamic load testing shall be analysed to remove
the effects of dynamic soil dependent behaviour before it can be considered equivalent to the ultimate measured
compressive resistance as outlined in the appropriate Annex.
3.1.15
design compressive static resistance
ultimate compressive resistance of a pile
Note 1 to entry: This shall be determined prior to load testing to allow specification of the appropriate magnitude
of dynamic load test.
3.1.16
equivalent diameter
diameter of the circle of which the area equals the area of the relevant pile section
Note 1 to entry: The equivalent diameter for a circular pile is the outer diameter of the pile, for a square pile the
diameter which gives the same area as the square pile (as long as the longest side is smaller than 1,5 times the
shortest side) is the equivalent diameter.
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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

3.1.17
minimum reference separation distance
distance which separates a stationary reference point from a point that will be significantly displaced
by the testing method
Note 1 to entry: Only stationary points can be used for reference of displacement measurement devices.
Displacement measuring systems can be placed on the soil outside the reference distance without isolating
(displacement compensating) measures.
3.1.18
displacement
axial movement of the pile head measured during testing
3.2 Symbols
a acceleration
A cross-sectional area of the pile at the level being considered
A cross-sectional area of the pile reinforcement at the level being considered
r
c velocity of the stress wave in the test pile
E Young's modulus of the pile material at the measurement level being considered
dyn
E kinetic energy
k
E potential energy
p
F force at the pile head derived from strain measurements
f the characteristic yield strength of the pile reinforcement
yk
2
g acceleration due to gravity (g = 9,8 m/s )
h drop height (or stroke) the mass or hammer has fallen through
L pile length
m mass
R measured ultimate compressive resistance of the ground in the test, or measured geotechni-
c,m
cal resistance of the pile
t time
v velocity
Z pile impedance
w pile displacement or settlement
ε strain
4 Testing equipment
4.1 General
The loading equipment shall be able to generate sufficient force and energy to be able to mobilize the
compressive resistance to be verified.
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SIST EN ISO 22477-4:2018
ISO 22477-4:2018(E)

If information on the ultimate measured compressive resistance of the pile is one of the aims of the test,
the equipment shall have enough capacity to reach the ultimate measured compressive resistance and
mobilize adequate settlement under dynamic loading with a single or a sequence of single blows.
The maximum pile load during a dynamic load test required to determine the ultimate measured
compressive resistance can exceed the design compressive static resistance. The need to apply such
high loads shall be considered when specifying equipment and pile materials.
If for a dynamic load test, one or more of the requirements in this document is not met; it should be
proven that this shortcoming has no influence on the achievement of the objectives of the test, before
the results can be interpreted as a dynamic load test.
Dynamic load testing systems rely on a mass to apply load to the head of the pile. This is either as
part of a pile driving hammer referred to as an impact driving system or by dropping a mass, referred
to as a drop mass system. Dynamic load testing can be undertaken during pile installation of precast
concrete piles or steel piles (displacement piles) when driving with a hammer. Drop mass systems are
used for the testing of cast-in-situ piles (bored piles, continuous flight auger or other cast-in-situ piles)
or testing associated with re-driving. The type of load application used during testing can depend on
several factors including the availability of pile installation or loading equipment and the phase of the
construction project.
Three types of dynamic pile tests are given in EN1997 -1: 2004+A1: 2013 which relate to the type of
measurements and analysis undertaken and are referred to as dynamic impact tests, pile driving
formula and wave equation analysis. These together with the multi-blow dynamic testing technique
are presented in more detail in the annexes. The measurements taken, equipment and information
required for a dynamic load test will be dependent on the specific dynamic load test being undertaken.
4.2 Loading
4.2.1 General
The selection of the loading equipment shall take into account:
— the aim of the test;
— the type of dynamic test and the analysis to be undertaken;
— the pile type;
— the ground conditions;
— the maximum pile load;
— the strength of the pile (material) and permissible stresses it can carry;
— the execution of the test;
— safety considerations.
The loading equipment shall generate adequate force and energy which fulfils the requirements in
4.1 and is able to apply the required maximum compressive force to mobilize a specified compressive
resistance or the ultimate measured compressive resistance of a pile. The equipment shall load the
pile accurately with appropriate guidance of the drop mass along the direction of the pile axis. The
eccentricity of the load shall be smaller than 10 % of the equivalent diameter. The deviation of the
alignment of the force to the axis of the pile shall be smaller than 20 mm/m.
The stress generated in the pile under the maximum applied load shall not exceed the permissible
stress of the pile material. For concrete piles in compression the maximum stress in the pile, including
any prestress in the pile, shall not exceed 0,8 times the characteristic concrete strength in compression
at the time of driving (as outlined in EN 12699). For concrete piles in tension the tensile force induced
© ISO 2018 – All rights reserved 5

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