EN ISO 15630-3:2002

SLOVENSKI STANDARD
SIST EN ISO 15630-3:2003
01-april-2003
Jeklo za armiranje in prednapenjanje betona - Metode preskušanja - 3. del: Jeklo
za prednapenjanje (ISO 15630-3:2002)
Steel for the reinforcement and prestressing of concrete - Test methods - Part 3:
Prestressing steel (ISO 15630-3:2002)
Stähle für die Bewehrung und das Vorspannen von Beton - Prüfverfahren - Teil 3:
Spannstähle (ISO 15630-3:2002)
Aciers pour l'armature et la précontrainte du béton - Méthodes d'essai - Partie 3:
Armatures de précontrainte (ISO 15630-3:2002)
Ta slovenski standard je istoveten z: EN ISO 15630-3:2002
ICS:
77.140.15 Jekla za armiranje betona Steels for reinforcement of
concrete
SIST EN ISO 15630-3:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 15630-3:2003

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SIST EN ISO 15630-3:2003
EUROPEAN STANDARD
EN ISO 15630-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2002
ICS 77.140.99; 91.080.40
English version
Steel for the reinforcement and prestressing of concrete - Test
methods - Part 3: Prestressing steel (ISO 15630-3:2002)
Aciers pour l'armature et la précontrainte du béton - Stähle für die Bewehrung und das Vorspannen von Beton -
Méthodes d'essai - Partie 3: Armatures de précontrainte Prüfverfahren - Teil 3: Spannstähle (ISO 15630-3:2002)
(ISO 15630-3:2002)
This European Standard was approved by CEN on 11 April 2002.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2002 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15630-3:2002 E
worldwide for CEN national Members.

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SIST EN ISO 15630-3:2003
EN ISO 15630-3:2002 (E)
CORRECTED  2002-06-05
Foreword
This document (ISO 15630-3:2002) has been prepared by Technical Committee ISO/TC 17
"Steel" in collaboration with Technical Committee ECISS/TC 19 "Concrete reinforcing and
prestressing steels - Properties, dimensions, tolerances and specific tests", the secretariat of
which is held by DIN.
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 2002, and conflicting national
standards shall be withdrawn at the latest by October 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the
United Kingdom.
Endorsement notice
The text of the International Standard ISO 15630-3:2002 has been approved by CEN as a
European Standard without any modifications.
NOTE Normative references to International Standards are listed in annex ZA (normative).
2

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SIST EN ISO 15630-3:2003
EN ISO 15630-3:2002 (E)
Annex ZA
(normative)
Normative references to international publications
with their relevant European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions
of any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications,
indicated by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 4287 1997 Geometrical product specifications EN ISO 4287 1998
(GPS) - Surface texture: Profile
method - Terms, definitions and
surface texture parameters
ISO 6508-1 1999 Metallic materials - Rockwell EN ISO 6508-1 1999
hardness test - Part 1: Test method
(scales A, B, C, D, E, F, G, H, K, N,
T)
ISO 7438 1985 Metallic materials - Bend test EN ISO 7438 2000
ISO 7500-1 1999 Metallic materials - Verification of EN ISO 7500-1 1999
static uniaxial testing machines -
Part 1: Tension/compression testing
machines
3

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SIST EN ISO 15630-3:2003

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SIST EN ISO 15630-3:2003


INTERNATIONAL ISO
STANDARD 15630-3
First edition
2002-04-15


Steel for the reinforcement and
prestressing of concrete — Test
methods —
Part 3:
Prestressing steel
Aciers pour l'armature et la précontrainte du béton — Méthodes d'essai —
Partie 3: Armatures de précontrainte




Reference number
ISO 15630-3:2002(E)
©
 ISO 2002

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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
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©  ISO 2002
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic
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ii © ISO 2002 – All rights reserved

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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope .1
2 Normative references.1
3 Symbols.2
4 General provisions concerning test pieces.3
5 Tensile test .4
6 Bend test .5
7 Reverse bend test.6
8 Isothermal stress relaxation test .6
9 Axial load fatigue test.9
10 Stress corrosion test in a solution of thiocyanate.11
11 Deflected tensile test.13
12 Chemical analysis.17
13 Measurement of the geometrical characteristics.17
14 Determination of the relative rib area (f ) .20
R
15 Determination of deviation from nominal mass per metre.21
16 Test report .21

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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
The main task of technical committees is to prepare International Standards. Draft International Standards adopted
by the technical committees are circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO 15630 may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 15630-3 was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 16, Steels for the
reinforcement and prestressing of concrete.
This part of ISO 15630, together with parts 1 and 2, cancels and replaces ISO 10065:1990, ISO 10287:1992 and
ISO 10606:1995.
ISO 15630 consists of the following parts, under the general title Steel for the reinforcement and prestressing of
concrete — Test methods:
 Part 1: Reinforcing bars, wire rod and wire
 Part 2: Welded fabric
 Part 3: Prestressing steel
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
Introduction
The aim of ISO 15630 is to provide all relevant test methods for reinforcing and prestressing steels in one standard.
In that context, the existing International Standards for testing these products have been revised and updated.
Some further test methods have been added.
Reference is made to International Standards on testing of metals in general as they are applicable.
Complementary provisions have been given if needed.
Test methods which do not form the subject of an existing International Standard on metal testing are fully
described in ISO 15630.

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SIST EN ISO 15630-3:2003

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SIST EN ISO 15630-3:2003
INTERNATIONAL STANDARD ISO 15630-3:2002(E)

Steel for the reinforcement and prestressing of concrete — Test
methods —
Part 3:
Prestressing steel
1 Scope
This part of ISO 15630 specifies test methods applicable to prestressing steels (bar, wire or strand).
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 15630. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 15630 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
ISO 4287:1997, Geometrical Product Specification (GPS) — Surface texture: Profile method — Terms, definitions
and surface texture parameters
ISO 4965:1979, Axial load fatigue testing machines — Dynamic force calibration — Strain gauge technique
ISO 6508-1:1999, Metallic materials — Rockwell hardness test — Part 1: Test method (scales A, B, C, D, E, F, G,
H, K, N, T)
ISO 6892:1998, Metallic materials — Tensile testing at ambient temperature
ISO 7438:1985, Metallic materials — Bend test
ISO 7500-1:1999, Metallic materials — Verification of static uniaxial testing machines — Part 1:
Tension/compression testing machines — Verification and calibration of the force-measuring system
ISO 7801:1984, Metallic materials — Wire — Reverse bend test
ISO 9513:1999, Metallic materials — Calibration of extensometers used in uniaxial testing
ISO/TR 9769:1991, Steel and iron — Review of available methods of analysis
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
3 Symbols
See Table 1.
Table 1 — Symbols
Symbol Unit Description Reference
a
mm Rib height at the mid-point 13.3, 14.2
m
a mm Maximum height of rib or depth of indentation 13.3
max
a
mm Average height of a portion i of a rib subdivided in p parts of length ∆l 14.2
s, i
a
mm Rib height at the quarter-point 13.3, 14.2
1/4
a mm Rib height at the three-quarters point 13.3, 14.2
3/4
A
% Percentage total elongation at maximum force 5
gt
c mm Rib or indentation spacing 13.3
C Groove width at nominal diameter of the mandrel, d , used for the deflected tensile
mm 11.3.4
a
test
d mm Nominal diameter of the bar, wire or strand 9.2, 9.4.6,
10.3.4
d
mm Nominal diameter of the mandrel used for the deflected tensile test 11.3.4
a
d mm Diameter with 2 gauge cylinders in the groove of the mandrel used for the deflected 11.3.4
b
tensile test
d mm Diameter of the gauge cylinder used for the deflected tensile test 11.3.4
e
d
mm Inner diameter of the groove of the mandrel used for the deflected tensile test 11.3.4
i
D % Average coefficient of reduction of the maximum force in the deflected tensile test 11.2, 11.4
D mm Inner diameter of the cell in the stress corrosion test 10.3.4
c
D % Individual percentage of reduction of the maximum force in the deflected tensile test 11.4
i
e
mm Average gap between two adjacent rib or indentation rows 13.3.1.4,
13.3.2.4
2
E Modulus of elasticity 5.3
N/mm
f
Hz Frequency of load cycles in the axial load fatigue test 9.1, 9.4.2
f 1 Relative rib area Clause 14
R
F
N Individual breaking force in the deflected tensile test 11.4
a, i
F N Maximum force 5.3
m
F N Mean value of the maximum force 8.2, 10.2, 11.2
m, m
F N 0,1 % proof force 5.3
p0,1
F N 0,2 % proof force 5.3
p0,2
F N Force range in the axial load fatigue test 9.1, 9.3, 9.4.2
r
F N Residual force in the test piece at time t in the relaxation test 8.1
rt
∆F N Force loss in the test piece at time t in the relaxation test 8.1
rt
2
F Area of longitudinal section of a rib 14.2
mm
R
F N Upper force in the axial load fatigue test 9.1, 9.3, 9.4.2
up

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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
Table 1 (continued)
Symbol Unit Description Reference
F N Initial force in the isothermal stress relaxation test and the stress corrosion test 8.1, 8.3, 8.4,
0
10.4.2
G
mm Depth of the groove of the mandrel used for the deflected tensile test 11.3.4
h mm Bow height in the plane of the bow 13.3.4
b
L
mm Length of the test piece in the stress corrosion test 10.2
t
L mm Gauge length (without force on the test piece) in the isothermal stress relaxation test 8.1, 8.3, 8.4
0
Length of the test piece in contact with the solution in the stress corrosion test 10.2, 10.3.4,
10.4.5
Elongation of the gauge length, L , under force, F , in the isothermal stress relaxation
∆L mm 8.1, 8.3, 8.4
0 0
0
test
L mm Length of the passive side in the deflected tensile test 11.3.2
1
L mm Length of the active side in the deflected tensile test 11.3.2
2
P mm Lay length of a strand 13.3.3
R mm Radius at the base of the mandrel used for the deflected tensile test 11.3.4
Ra µm Surface roughness of the mandrel used for the deflected tensile test 11.3.4
2
S
Nominal cross-sectional area of the test piece 5.3.2
mm
n
t h Maximum agreed time for the stress corrosion test 10.4.5
a
t h Individual lifetime to fracture in the stress corrosion test 10.4.5
f, i
t
h Median lifetime to fracture in the stress corrosion test 10.4.6
f, m
t s Starting time in the isothermal stress relaxation test and in the stress corrosion test 8.4.2, 10.4
0
3
V Volume of test solution to fill the test cell in the stress corrosion test 10.4.3
mm
0
α ° Angle of deviation in the deflected tensile test 11.3.2
° Rib or indentation angle to the bar or wire axis 13.3
β
% Relaxation 8.4.8
ρ
Σe mm Part of the circumference without indentation or rib 13.3.1.4,
i
13.3.2.4, 14.2
2
NOTE 1 N/mm = 1 MPa.

4 General provisions concerning test pieces
Unless otherwise agreed, the pieces shall be taken from the finished product normally before packaging.
Special care should be taken when sampling is made from the packaged product (e.g. coil or bundle), in order to
avoid plastic deformation which could change the properties of the samples used to provide the test pieces.
NOTE Specific complementary provisions concerning the test pieces may be indicated in the relevant clauses, when
applicable.
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
5 Tensile test
5.1 Test piece
The general provisions given in clause 4 apply.
5.2 Test equipment
The test equipment shall be verified and calibrated in accordance with ISO 7500-1 and shall be at least of class 1.
When an extensometer is used, it shall be of class 1 (see ISO 9513) for the determination of F or F ; for the

p0,1 p0,2
determination of A , a class 2 extensometer (see ISO 9513) may be used.
gt
Suitable grips shall be used to avoid breaks in or very near the grips.
5.3 Test procedure
5.3.1 General
The tensile test shall be carried out in accordance with ISO 6892:1998.
An extensometer shall be used for the determination of the modulus of elasticity (E), 0,1 % and 0,2 % proof force
(F and F ) and percentage total elongation at maximum force (A ). The extensometer gauge length shall be
p0,1 p0,2 gt
as given in the relevant product standard.
NOTE 1  Accurate values of A can only be obtained with an extensometer. If it is not possible to leave the extensometer on
gt
the test piece to fracture, the elongation may be measured as follows:
 continue loading until the extensometer records an elongation just greater than the elongation corresponding to F , at
p0,2
which the extensometer is removed and the distance between the testing machine cross-heads noted. The loading is
continued until fracture occurs. The final distance between the cross-heads is noted;
 the difference between the cross-heads measurements is calculated as a percentage of the original distance between the
cross-heads and this value is added to the percentage obtained by extensometer.
For wire and bars, it is also permissible to determine A by drawing equidistant marks on the free length of the test piece (see
gt
annex H of ISO 6892:1998). The distance between the marks should be 20 mm, 10 mm or 5 mm, depending on the wire or bar
diameter.
NOTE 2 It is preferable to preload the test piece, e.g. to about 0,1 of the expected maximum force before placing the
extensometer.
If A is not completely determined with an extensometer, this shall be indicated in the test report.
gt
Tensile properties, F , F , F , are recorded in force units.
p0,1 p0,2 m
When the rupture occurs within a distance of 3 mm from the grips, the test shall, in principle, be considered as
invalid and it shall be permissible to carry out a retest. However, it shall be permitted to take into account the test
results if all values are greater than or equal to the relevant specified values.
5.3.2 Determination of the modulus of elasticity
The modulus of elasticity (E) shall be determined from the slope of the linear portion of the force-extension diagram
in the range between 0,2 F and 0,7 F divided by the nominal cross-sectional area of the test piece (S ).
m m n
The slope may be calculated either by a linear regression of the measured data stored in a data storage facility or
by a best fit visual technique over the above defined portion of the registered curve.
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
NOTE In some special cases, e.g. hot-rolled and stretched bars, the above mentioned method cannot be applied; a secant
modulus between 0,05 F and 0,7 F may then be determined.
m m
In addition to the provisions given in 5.3.1, it shall be ensured that the stress rate shall not be changed within the
force range over which the modulus of elasticity is determined.
6 Bend test
6.1 Test piece
The general provisions given in clause 4 apply.
6.2 Test equipment
6.2.1 A bending device, the principle of which is shown in Figure 1, shall be used.
NOTE Figure 1 shows a configuration where the mandrel and support rotate and the carrier is locked. It is also possible
that the carrier rotates and the support or mandrel is locked.

Key
1 Mandrel
2 Support
3 Carrier
Figure 1 — Principle of a bending device
6.2.2 The bend test may also be carried out by using a device with supports and a mandrel (see 4.1 of
ISO 7438:1985).
6.3 Test procedure
The bend test shall be carried out at a temperature between 10 °C and 35 °C. The test piece shall be bent over
a mandrel.
NOTE The bending rate should be about 60°/s.
The angle of bend and the diameter of the mandrel shall be in accordance with the relevant product standard.
6.4 Interpretation of test results
The interpretation of the bend test shall be carried out according to the requirements of the relevant product
standard.
When these requirements are not specified, the absence of cracks visible to a person with normal or corrected
vision is considered as evidence that the test piece withstood the bend test.
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
7 Reverse bend test
7.1 Test piece
In addition to the general provisions given in clause 4, the test piece shall comply with clause 5 of ISO 7801:1984.
7.2 Test equipment
The test equipment shall comply with clause 4 of ISO 7801:1984.
7.3 Test procedure
The reverse bend test shall be carried out according to ISO 7801:1984.
8 Isothermal stress relaxation test
8.1 Principle of test
The isothermal stress relaxation test consists of measuring, at a given temperature (generally fixed at 20 °C unless
otherwise agreed) the variations of force of a test piece maintained at constant length (L + ∆L ), from an initial
0 0
force (F ) (see Figure 2).
0
The loss in force is expressed as a percentage of the initial force for a given period of time.

Figure 2 — Principle of the isothermal stress relaxation test
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
8.2 Test piece
The general provisions given in clause 4 apply.
The test piece for the relaxation test shall be maintained in a straight condition. The free length of the test piece
between the grips shall not be subjected to any mechanical deformation or treatment of any kind.
Two test pieces adjacent to the test pieces for the stress relaxation test shall be taken for the determination of the
mean value of maximum force (F ), when the initial force, F , is expressed as a percentage of F , e.g. 70 %
m, m 0 m, m
F .
m, m
8.3 Test equipment
8.3.1 Frame
Any deformation of the frame shall be within such limits that it does not influence the results of the test.
8.3.2 Force-measuring device
The force shall be measured either by a coaxial load cell or another appropriate device (e.g. lever loading system).
The load cell shall be calibrated in accordance with ISO 7500-1:1999 and have an accuracy of ± 1 % for forces up
to 1 000 kN and ± 2 % for forces greater than 1 000 kN.
Any other appropriate device shall provide the same accuracy as the one specified for the load cell.
−4
The resolution of the output of the force-measuring device shall be 5 × 10 F or better.
0
8.3.3 Length measuring device (extensometer)
The gauge length (L ) shall be not less than 200 mm and particularly for strands, should preferably be of the order
0
of 1 000 mm or of an integer number of the strand lay length when the actual length (L + ∆L ) is measured on the
0 0
same wire of the strand. The extensometer shall have an accuracy of at least ± 1 % and shall have an output or
−6
calibration of scale capable of a resolution of 5 × 10 L
.
0
8.3.4 Anchoring device
The anchoring device shall be constructed in such a way that slipping during the test is either not possible or is
corrected and rotation is prevented.
8.3.5 Loading device
The loading device shall allow smooth increase of loading the test piece without shock. It shall be constructed in
such a way that the length (L + ∆L ) can be maintained within the limits fixed in 8.4.5, throughout the test, by
0 0
reduction of force.
8.4 Test procedure
8.4.1 Provisions concerning the test piece
The test piece shall stay at least 24 h in the testing laboratory prior to the test.
The test piece shall be securely gripped in the anchorages of the test device in order to avoid any slip during
loading and during the test.
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
8.4.2 Application of force
Application of force shall at all times be carried out smoothly and without shock.
The loading up to 20 % of the initial force, F , may be carried out as desired. Loading of the test piece from 20 %
0
up to 80 % of F shall be applied continuously or in three or more uniform steps or with a uniform rate of loading
0
and shall be completed within 6 min. Application of the force between 80 % and 100 % of F shall be continuous
0
and shall be completed within 2 min, after achievement of 80 % of F .
0
On attainment of the initial force, F , the force shall be kept constant for a period of 2 min. Immediately on
0
completion of this 2 min period, time, t , is established and recorded. Any subsequent adjustment of force shall
0
only be made in order to ensure that L + ∆L is kept constant.
0 0
The application of force is illustrated schematically in Figure 3.

Figure 3 — Application of force in the relaxation test
8.4.3 Initial force
The initial force shall be as specified in the appropriate product standard. The measured value of the initial force
shall be within the tolerances of the specified value given in Table 2.
Table 2 — Tolerance of F
0
Value of F Tolerance of F
0 0
F u 1 000 kN ± 1 %
0
F > 1 000 kN
± 2 %
0

8.4.4 Force during the test
At any time the force shall not be permitted to exceed the initial force by more than the tolerances given in Table 2.
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SIST EN ISO 15630-3:2003
ISO 15630-3:2002(E)
8.4.5 Maintenance of strain
The strain imposed by the initial force, F , at time, t , shall be meas
...