ISO 10406-2:2015

INTERNATIONAL ISO
STANDARD 10406-2
Second edition
2015-01-15
Fibre-reinforced polymer (FRP)
reinforcement of concrete — Test
methods —
Part 2:
FRP sheets
Polymère renforcé par des fibres (PRF) pour l’armature du béton —
Méthodes d’essai —
Partie 2: Feuilles en PRF
Reference number
©
ISO 2015
© ISO 2015
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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Published in Switzerland
ii © ISO 2015 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Definitions . 1
3.2 Symbols . 3
4 General provision concerning test pieces . 5
5 Test method for determining tensile properties . 5
5.1 Test pieces . 5
5.2 Testing machine and measuring devices . 9
5.3 Test method . 9
5.4 Calculation and expression of test results .10
5.5 Test report .11
6 Test method for overlap splice strength .12
6.1 Test pieces .12
6.2 Testing machine .14
6.3 Test method .14
6.4 Calculation and expression of test results .15
6.5 Test report .15
7 Test method for determining bond properties of FRP sheets to concrete .16
7.1 Test pieces .16
7.2 Testing machine and measuring devices .21
7.3 Test method .21
7.4 Calculation and expression of test results .21
7.5 Test report .22
8 Test method for direct pull-off strength of FRP sheets with concrete .23
8.1 Test pieces .23
8.2 Testing machine and measuring devices .25
8.3 Test method .25
8.4 Calculation and expression of test results .25
8.5 Test report .26
9 Test method for freeze/thaw resistance .26
9.1 Test pieces .26
9.2 Testing machine and measuring devices .26
9.3 Test method .27
9.4 Calculation and expression of test results .27
9.5 Test report .28
10 Test method for exposure to laboratory light sources .29
10.1 Test pieces .29
10.2 Testing machine and measuring devices .29
10.3 Test method .30
10.4 Calculation and expression of test results .30
10.5 Test report .31
11 Test method for durability .32
11.1 Types of test methods for durability .32
11.2 Test piece .32
11.3 Test method .33
11.4 Calculation and expression of test results .34
11.5 Test report .34
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.
The committee responsible for this document is ISO/TC 71, Concrete, reinforced concrete and pre-stressed
concrete, Subcommittee SC 6, Non-traditional reinforcing materials for concrete structures.
This second edition cancels and replaces the second edition (ISO 10406:2008), which has been technically
revised.
ISO 10406 consists of the following parts, under the general title Fibre-reinforced polymer (FRP)
reinforcement of concrete — Test methods:
— Part 1: FRP bars and grids
— Part 2: FRP sheets
iv © ISO 2015 – All rights reserved

INTERNATIONAL STANDARD ISO 10406-2:2015(E)
Fibre-reinforced polymer (FRP) reinforcement of
concrete — Test methods —
Part 2:
FRP sheets
1 Scope
This part of ISO 10406 specifies test methods applicable to fibre-reinforced polymer (FRP) sheets for
the upgrading of concrete members.
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 31-0:1992, Quantities and units — Part 0: General principles
ISO 291, Plastics — Standard atmospheres for conditioning and testing
ISO 4892 (all parts), Plastics — Methods of exposure to laboratory light sources
ISO 5725 (all parts), Accuracy (trueness and precision) of measurement methods and results
ISO 7500-1, Metallic materials — Verification of static uniaxial testing machines — Part 1: Tension/compression
testing machines — Verification and calibration of the force-measuring system
3 Terms and definitions
3.1 Definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
accelerated artificial exposure testing machine
machine that creates reproducible standard test conditions to accelerate weathering artificially
3.1.2
ambient temperature
environmental conditions corresponding to the usual atmospheric conditions in laboratories with
uncontrolled temperature and humidity
3.1.3
anchorage block
block corresponding to the test block to prevent bond failure of the FRP sheet
Note 1 to entry: Additional FRP sheet circumferentially jackets the block with sheets being tested to provide
higher bond strength (in this block).
3.1.4
anchoring portion
end parts of a test piece fitted with anchoring devices to transmit loads from the testing machine to the
test portion
3.1.5
bond strength
strength calculated by dividing the maximum load by the effective bond area
3.1.6
concrete block
rectangular block of concrete used to study the bond properties of FRP sheets to concrete
Note 1 to entry: Steel reinforcement or steel bars are embedded in the axial direction at the centre of the cross-
sectional area of the concrete block in order to transmit tensile strength. Concrete blocks are made up of a test
block and an anchorage block.
3.1.7
conditioning
storage of test pieces at a prescribed temperature and humidity to keep them under identical conditions
before testing
3.1.8
coupon test piece
test piece selected from the same lot that is unexposed and subjected to the tensile strength and overlap
splice strength tests
3.1.9
effective bond area
area estimated using the effective bond length and the bond width of the FRP sheet
3.1.10
effective bond length
length of the portion in which the bond stress between the FRP sheet and the concrete acts effectively
at maximum load before the FRP sheet comes loose from the concrete
3.1.11
fibre bundle
several fibre filaments bound together to form a bundle
3.1.12
fibre mass per unit area
mass of fibre in the direction of reinforcement in dry sheet (fibre sheets before impregnation with resin)
Note 1 to entry: Expressed as mass per square metres.
3.1.13
interfacial fracture energy
amount of energy per unit bond area necessary to produce interfacial fracture
3.1.14
overlap splice strength retention rate
ratio of the overlap splice strength after accelerated artificial exposure or freezing/thawing compared
with the overlap splice strength before accelerated artificial exposure or freezing/thawing
Note 1 to entry: The overlap splice strength retention is rate expressed as a percentage.
3.1.15
plate
FRP sheet impregnated with resin from which the test pieces are cut
2 © ISO 2015 – All rights reserved

3.1.16
pull-out strength
strength calculated by dividing the maximum load by the cross-sectional area of the bond surface of the
steel device
3.1.17
steel device
mechanism made of steel connected to a loading machine to apply tensile force
Note 1 to entry: Adhesive is used to mount the device to the FRP sheet attached to the concrete surface. The shape
of the bond surface is either square or circular.
3.1.18
tab
plate made of fibre-reinforced polymer, aluminium, or any other suitable material bonded to the test
piece to transmit loads from the testing machine to the test portion
3.1.19
tensile capacity
maximum tensile load which the test piece bears during the tensile test
3.1.20
tensile strength retention rate
ratio of the tensile strength after accelerated artificial exposure or freezing/thawing compared with
the tensile strength before accelerated artificial exposure or freezing/thawing
Note 1 to entry: The tensile strength retention rate is expressed as a percentage.
3.1.21
test block
block used to study the bond properties of FRP sheets
3.1.22
test portion
part of a test piece that is in between the anchoring portions and is subjected to testing
3.1.23
ultimate strain
strain corresponding to the tensile capacity
3.1.24
weathering
physical and chemical changes of material properties due to exposure to sunlight, rain, snow, and other
outdoor natural conditions
3.2 Symbols
See Table 1.
Table 1 — Symbols
Symbol Unit Description Reference
A mm Nominal cross-sectional area (general) 5.4
A mm Nominal cross-sectional area of type A test piece 5.4, 6.4
A
A mm Nominal cross-sectional area of type B test piece 5.4, 6.4
B
A mm Area of steel device 8.4
s
b mm Average width of FRP sheet 7.4
av
Table 1 (continued)
Symbol Unit Description Reference
b mm Minimum width of test piece 5.4, 6.4
t,min
E N/mm Young’s modulus 5.4, 7.4
f
f N/mm Bond strength 8.4
au
f N/mm Tensile strength 5.4
fu
N/mm Average value for tensile strength before treating, e.g. 9.4, 10.4
f
fu0
freezing and thawing or accelerated artificial exposure
f N/mm Average value for tensile strength after treating, e.g. freez- 9.4, 10.4
fu1
ing and thawing or accelerated artificial exposure
f N/mm Overlap splice strength 6.4
fus
N/mm Average value for overlap splice strength before treating, 9.4, 10.4
f
fus0
e.g. freezing and thawing or accelerated artificial exposure
N/mm Average value for overlap splice strength after treating, 9.4, 10.4
f
fus1
e.g. freezing and thawing or accelerated artificial exposure
F N Maximum load 8.4
au
F N The load included in the last simultaneously recorded pair 5.4.5
last
of values of the load and the strain when determining the
ultimate strain
F N Tensile capacity 5.4, 6.4
u
G N/mm Interfacial fracture energy 7.4
f
L mm Anchoring portion length 5.1.1
A1
L mm Anchorage thickness 5.1.1
A2
L mm Anchorage length 5.1.1
A3
L mm Width at both ends 5.1.1
end
L mm Gauge length 5.1.1
ga
L mm Thickness 5.1.1
th
L mm Total length 5.1.1
tot
l mm Effective bond length in test portion of FRP sheet 7.4
N — Number of fibre bundles in test piece 5.4
t
n — Number of plies of the sheet 7.4
n strands/mm Number of fibre bundles per unit area of the sheet 5.4
u
P N Maximum load 7.4
max
R % Overlap splice strength retention 9.4
ets
R % Tensile strength retention 9.4
ett
−3
t mm 7.4
Thickness of sheet, equal to n·ρρ ×10
Ssh
ΔF N Difference between loads at two points at 20 % and 50 % 5.4
of tensile capacity
ρ g/m Fibre mass per unit area of dry sheet 5.4, 6.4, 7.4
S
ρ g/cm Density of dry sheet 5.4, 6.4, 7.4
sh
ε — The strain included in the last simultaneously recorded 5.4.5
last
pair of values of the load and the strain when determining
the ultimate strain
4 © ISO 2015 – All rights reserved

Table 1 (continued)
Symbol Unit Description Reference
ε — Difference in strain between the two points used to calcu- 5.4.5
fu
late ΔF
Δε
— Ultimate strain 5.4
τ N/mm Bond strength 7.4
u
4 General provision concerning test pieces
Unless otherwise agreed upon, test pieces shall be taken from the sheet in the “as delivered” condition.
For the determination of the mechanical properties in the tensile, bond, and anchorage tests, the
test piece may be artificially aged (after straightening, if applicable) depending on the performance
requirements of the product.
When a test piece is “aged”, the conditions of the ageing treatment shall be stated in the test report.
5 Test method for determining tensile properties
5.1 Test pieces
5.1.1 Types and dimensions
Two types of test pieces may be used (see Figure 1 and Table 2).
a) Type A test pieces: Prepare type A test pieces in accordance with the method described in 6.1.2.1
and use them for the general tension test. The shape and the dimensions of type A test pieces are
given in Figure 1 and Table 2, respectively.
b) Type B test pieces: Prepare type B test pieces in accordance with the method described in 6.1.2.2.
These test pieces are suitable for FRP sheets in which the fibre bundles consist of a number of
filaments that can be easily separated into individual bundles.
L
tot
L
ga
L L
A1 A1
L L
A3 A3
NOTE See Table 2 for definitions of symbols and dimensions.
Figure 1 — Shape of type A and type B test pieces
L L
th end
L
A2
Table 2 — Dimensions of test pieces
Dimensions in millimetres
Dimension for the types of test piece
Symbol
Type A Type B
L total length ≥200
tot
L width at both ends 12,5 ± 0,5 10 to 15
end
L thickness Recommended not to exceed 2,5
th
L gauge length ≥100
ga
L anchoring portion length ≥35
A1
L anchorage thickness 1 to 2
A2
L anchorage length ≥50
A3
NOTE When the peeling off at tabs and the pull-out in the chuck do not occur, the thickness
of the test piece can exceed 2,5 mm. When the thickness of the test piece is less than 2,5 mm
and fracture at anchoring section occurs, the specification of the anchoring section should be
reconsidered.
5.1.2 Preparation
5.1.2.1 Type A test pieces
Type A test pieces shall be prepared using the following method.
a) Prepare a dry sheet cut to a sufficient length for the test piece.
b) Apply the bottom coat of impregnation resin to the separation film and attach the aforementioned
sheet, fastening it so that the fibre axis of the sheet is in a straight line.
c) Apply the top coat of impregnation resin then smooth the surface so that the thickness of the
impregnation resin layer is even, to form a plate. Covering with separation film and smoothing
would be best.
d) Cure the plate for the prescribed duration considering manufacturer’s instructions, then cut in
widths of 12,5 mm as shown in Figure 2. The cut length should be at least 200 mm. Use a diamond
cutter for cutting.
e) Attach the anchorages to the anchorage portions to form the test pieces.
f) Prior to testing, the test pieces shall be conditioned as prescribed in 5.1.5 considering manufacturer’s
instructions.
6 © ISO 2015 – All rights reserved

Dimensions in millimetres
ab
12,5
Key
1 direction of fibre axis
2 section used to prepare test piece: ≥200 (area impregnated with resin)
3 test piece portion
4 cut-away portion
5 marking
a, b
Location of the two straight-line marks perpendicular to the fibre axis that define a length of at least 200 mm.
Figure 2 — Dimensions of plate used to prepare type A test pieces
5.1.2.2 Type B test pieces
Type B test pieces shall be prepared using the following method.
a) Prepare a dry sheet cut to a sufficient length for the test piece. Fasten the sheet so that the fibre axis
is in a straight line.
b) In the centre of the fastened sheet, mark two straight lines (footnotes a and b in Figure 3)
perpendicular to the fibre axis that define a length of at least 200 mm. Mark two other straight lines
(footnotes c and d in Figure 3) approximately 100 mm on either side of the area defined by lines a
and b.
c) Working along the fibre axis between lines c and d, remove one to three fibre bundles from each side
of the test piece sections. The width measures 10 mm to 15 mm. When preparing several test pieces
from the same FRP sheet, the portions to be used as test pieces should be separated by intervals of
at least 50 mm in the direction perpendicular to the fibre axis.
d) Apply the bottom coat of impregnation resin to the separation film and attach the aforementioned
sheet onto the film.
e) Apply the topcoat of impregnation resin. Then smooth the surface, so that the thickness of the
impregnation resin layer is even, to form a plate. Covering with separation film and smoothing
would be best.
f) Cure the plate for the prescribed duration, then cut the fibre bundle portions that are to be the test
pieces at widths of 10 mm to 15 mm. The cut length shall be at least 200 mm.
g) Attach the anchorages to the anchorage portions to form the test pieces.
Dimensions in millimetres
100 3 100
c ab d
10-15 5
6 50
4 4
Key
1 direction of fibre axis
2 area impregnated with resin: ≥400
3 section used to prepare test piece: ≥200
4 marking
5 cut-away portion
6 test piece portion
a, b
Location of the two straight-line marks perpendicular to the fibre axis that define a length of at least 200 mm.
c, d
Location of the two straight-line marks at least 100 mm on either side of lines a and b.
Figure 3 — Dimensions of plate used to prepare type B test pieces
h) Prior to testing, condition the test pieces as prescribed in 5.1.5 considering manufacturer’s
instructions.
A tracer thread may be added to uncured, wet-laid material to help identify the fibre direction and
to somehow specify how accurately the specimens should be cut from the larger piece of material,
specifically with respect to the fibre direction.
5.1.3 Curing of test pieces
Establish the curing period needed to give the test piece the desired strength and cure the test piece
considering manufacturer’s instructions.
5.1.4 Anchorage portion of test pieces
The anchorage portion of the test piece shall not have a shape that causes the test piece to twist or bend.
An anchorage made of fibre-reinforced polymer or aluminium shall be attached to the anchorage portion
using resin or adhesive at a suitable pressure so that the thickness of the adhesive layer is constant. The
adhesive or resin shall ensure that the adhesive layer does not experience shear fracture before the test
piece breaks.
8 © ISO 2015 – All rights reserved

5.1.5 Conditioning of test pieces
The most appropriate condition from ISO 291 shall be selected, unless otherwise agreed upon by the
interested parties. If it is confirmed by prior tests under equivalence conditions at the testing room that
humidity has a negligible or no influence on the properties, it is not necessary to control the relative
humidity. Similarly, if it is confirmed by prior tests under equivalence conditions at the testing room
that neither temperature nor humidity has any noticeable influence on the properties, it is not necessary
to control either the temperature or the relative humidity. In this case, the atmospheric condition is
termed “ambient temperature”.
5.1.6 Number of test pieces
Determine the number of test pieces suitable for the objective of the test. It shall be no fewer than five.
5.2 Testing machine and measuring devices
5.2.1 Testing machine
The testing machine shall conform to ISO 7500-1. The testing machine shall have a loading capacity in
excess of the tensile capacity of the test piece and shall be capable of applying loading at the required
loading rate.
5.2.2 Strain gauges/extensometers
Strain gauges/extensometers used to measure the elongation of the test piece under loading should
be capable of recording all variations in the gauge length or elongation during testing with a strain
−6
measurement accuracy of at least 10 × 10 .
5.3 Test method
5.3.1 Dimensions of test pieces
Measure the width and thickness of the test portion of the test pieces as follows. The width and thickness
of the test piece shall be determined as the average of at least three readings taking from different
locations on the test specimen. Measurements shall be taken to the following precision:
a) test pieces of type A shall be measured to 0,01 mm;
b) test pieces of type B shall be measured to 0,1 mm.
5.3.2 Mounting of strain gauges/extensometers
Mount the strain gauges/extensometers at the centre of the test portion of the test piece in order to
determine the Young’s modulus and the ultimate strain of the test piece.
5.3.3 Mounting of test piece
Mount the test piece in such a way that the long axis of the test piece coincides with the centreline
between the two chucks.
5.3.4 Loading rate
The standard loading rate shall be a constant strain rate equivalent to 1 %/min to 3 %/min strain.
5.3.5 Test temperature
In principle, conduct the test in the same atmosphere used for conditioning the test piece, unless
otherwise agreed upon by the interested parties (e.g. for testing at elevated or low temperatures).
5.3.6 Range of test
Perform the loading test until tensile failure and record the measurements of load and strain continuously
or at regular intervals at least up to two thirds of the tensile capacity.
5.4 Calculation and expression of test results
5.4.1 General
Use only results from those pieces that undergo failure in the test portion. Reject the test results from
those pieces that show tensile failure or slippage at the anchorage portion and carry out additional tests
using test pieces from the same lot until the number of test pieces having failed in the test portion is not
less than the prescribed number.
5.4.2 Load-strain curve
When strain gauges/extensometers are mounted, plot a load-strain curve depicting the relationship
between the measured load and strain.
5.4.3 Tensile strength
Calculate the tensile strength, f , expressed in newtons per square millimetre and rounded off to three
fu
significant digits in accordance with ISO 31-0:1992, Annex B, using Formula (1):
F
u
f = (1)
fu
A
where
F is the tensile capacity, expressed in newtons;
u
A is the nominal cross-sectional area of the test piece, expressed in square millimetres.
Calculate the cross-sectional area, A , expressed in square millimetres, of the type A test piece using
A
Formula (2) and the cross-sectional area, A , expressed in square millimetres, of the type B test piece
B
using Formula (3):
ρ
−3
S
Ab=⋅ ×10 (2)
A t,min
ρ
sh
ρ N
S t −3
A =⋅ ×10 (3)
B
ρ n
sh u
where
ρ is the fibre mass per unit area of dry sheet, expressed in grams per square metres;
S
ρ is the density of dry sheet, expressed in grams per cubic centimetres;
sh
b is the minimum width of the test piece, expressed in millimetres;
t,min
N is the number of fibre bundles in the test piece;
t
n is the number of fibre bundles per unit area of the sheet, expressed in strands per millime-
u
tre.
NOTE 1 The nominal fibre mass per unit area provided by the material manufacturer can be used.
10 © ISO 2015 – All rights reserved

NOTE 2 The nominal density provided by the material manufacturer can be used.
5.4.4 Young’s modulus
Calculate the Young’s modulus, E , using Formula (4) based on the load-strain curve at 20 % and 50 %
f
tensile capacity and rounded off to three significant digits in accordance with ISO 5725 (all parts).
ΔF
E = (4)
f
Δε ⋅A
where
∆F is the difference between loads at two points at 20 % and 50 % tensile capacity, expressed in
newtons;
∆ε is the difference in strain between the two points above;
A is the nominal cross-sectional area, expressed in square millimetres, calculated as A , using
A
Formula (2), for a type A test piece and as A , using Formula (3), for a type B test piece.
B
5.4.5 Ultimate strain
In cases where strain-gauge measurements of the test piece are available up to the point of failure,
take the ultimate strain, ε , as the strain corresponding to the tensile capacity, F . In cases where the
fu u
measurements are not made up to the point of failure, calculate the ultimate strain, ε , using Formula (5),
fu
based on the tensile capacity, F , and the last simultaneously recorded values of the load, F , and
u last
strain, ε :
last
F
u
εε=⋅ (5)
fu last
F
last
Round off the results to three significant digits in accordance with ISO 5725 (all parts).
5.5 Test report
The test report shall include the following items:
a) name of FRP sheet, date of manufacture, lot number of production run, and name of manufacturer;
b) type of FRP sheet and impregnation resin;
c) fibre mass per unit area of dry sheet and density of dry sheet;
d) fabrication date, fabrication method, and curing conditions (including temperature and duration)
for test pieces;
e) temperature, humidity, and duration of test piece conditioning;
f) test date, test temperature, and loading rate;
g) dimensions of each test piece and calculated cross-sectional area;
h) tensile capacity of each test piece and average and, if required, the standard deviation for these
values;
i) tensile strength of each test piece and average and, if required, the standard deviation for these
values;
j) Young’s modulus of each test piece and average and, if required, the standard deviation for these
values;
k) ultimate strain of each test piece and average and, if required, the standard deviation for these
values;
l) load-strain curve for each test piece.
6 Test method for overlap splice strength
6.1 Test pieces
6.1.1 Dimensions
The shape and the dimensions of the overlap splice test piece are shown in Figure 4 and Table 3,
respectively. The method of preparing test pieces is described in 6.1.2.
NOTE Test piece corresponding to the Type A test piece in Clause 5 is specified in this part of ISO 10406. Type
B test piece is not specified because of difficulties of making test piece to keep axial direction of fibres linear in
two FRP sheets.
L
tot
L
ga
L
L SPI L
A1 A1
L L
A3 A3
NOTE See Table 3 for definitions of symbols and dimensions.
Figure 4 — Shape of test pieces
Table 3 — Dimensions of test pieces
Dimensions in millimetres
Symbol Dimension
L total length Length of splice plus a minimum of 200
tot
L width at both ends 12,5 ± 2,5
end
L thickness Recommended not to exceed 2,5
th
L gauge length Length of splice plus a minimum of 100
ga
L anchoring portion length ≥35
A1
L anchorage thickness 1 to 2
A2
L anchorage length ≥50
A3
L length of splice portion Necessary length
spl
NOTE When the peeling off at tabs and the pull-out in the chuck do not occur, the thickness
of the test piece can exceed 2,5 mm. When the thickness of the test piece is less than 2,5 mm
and fracture at anchoring section occurs, the specification of the anchoring section is to be
reconsidered.
12 © ISO 2015 – All rights reserved
L
L
end
th
L
A2
6.1.2 Preparation
As a rule, prepare test pieces using the same materials as those in the actual work and under constant
temperature conditions as follows, taking sufficient care to ensure that the fibres are not dispersed or
bent in the overlap splice portion.
a) Prepare a dry sheet cut to a sufficient length for the dimensions of the test piece to be fabricated.
b) Apply the bottom coat of impregnation resin to the separation film and attach the sheet mentioned
in a), fasten it so that the fibre axis of the sheet is in a straight line.
c) Overlap two sheets so that the prescribed length of the overlap splice portion is secured.
d) Apply the top coat of impregnation resin. Smooth the surface. The thickness of the impregnation
resin layer should be even to form a plate. Covering with separation film is best.
e) Cure the plate for the prescribed duration considering manufacturer’s instructions, then cut in
widths of 12,5 mm as shown in Figure 5. The cut length should be at least 200 mm. Use a diamond
cutter.
f) Attach the anchorage to the anchorage portion to form the test piece.
g) Before performing the test, condition the test piece as prescribed.
Dimensions in millimetres
a b
12,5
Key
1 direction of fibre axis
2 section used to prepare test piece: ≥200 (area impregnated with resin)
3 test piece portion
4 cut-away portion
5 marking
6 overlap splice section
a, b
Location of the two straight-line marks perpendicular to the fibre axis that define a length of at least 200 mm.
Figure 5 — Dimensions of plate used to make test pieces
6.1.3 Curing of test pieces
Establish the curing period for the test piece to have the desired strength and cure the test piece
considering the manufacturer’s instructions.
6.1.4 Anchorage portion of test pieces
The anchorage portion of the test piece shall not have a shape that causes the test piece to twist or bend.
Attach an anchorage made of fibre-reinforced plastic or aluminium to the anchorage portion using resin
or adhesive at a suitable pressure so that the thickness of the adhesive layer is constant. Ensure that the
adhesive or resin in the adhesive layer does not experience shear fracture before the test piece breaks.
6.1.5 Conditioning of test pieces
Select the most appropriate condition from ISO 291, unless otherwise agreed upon by the interested
parties. If it is confirmed by prior tests under equivalence conditions at the testing room that humidity
has a negligible or no influence on the properties, it is not necessary to control the relative humidity.
Similarly, if it is confirmed by prior tests under equivalence conditions at the testing room that neither
temperature nor humidity has any noticeable influence on the properties, it is not necessary to control
either the temperature or the relative humidity. In this case, the atmospheric condition is termed
“ambient temperature”.
6.1.6 Number of test pieces
Determine the number of test pieces suitable for the objective of the test. It shall be no fewer than five.
6.2 Testing machine
The testing machine shall conform to ISO 7500-1. The testing machine shall have a loading capacity in
excess of the tensile capacity of the test piece and shall be capable of applying loading at the required
loading rate.
6.3 Test method
6.3.1 Dimensions of test pieces
Measure the width and thickness of the test portion of the test pieces to 0,01 mm at four locations
outside the overlap splice portion and two locations within the overlap splice portion.
6.3.2 Mounting the test piece
Mount the test piece so that the long axis of the test piece coincides with the centre line between the two
chucks.
6.3.3 Loading rate
The standard loading rate shall be a fixed strain rate equivalent to 1 %/min to 3 %/min strain.
6.3.4 Test temperature
In principle, conduct the test in the same atmosphere used for conditioning the test piece, unless
otherwise agreed upon by the interested parties (e.g. for testing at elevated or low temperatures).
6.3.5 Range of test
Perform the loading test to the point of tensile failure and measure and record the load continuously or
at regular intervals until the tensile capacity is reached.
14 © ISO 2015 – All rights reserved

6.4 Calculation and expression of test results
6.4.1 General
Assess the test data only on the basis of the test pieces undergoing failure in the test portion. In cases
where tensile failure or slippage has clearly taken place at the anchorage portion, disregard the data and
perform additional tests using test pieces from the same lot until the number of test pieces failing in the
test portion is not less than the prescribed number.
6.4.2 Failure categories
Table 4 shows the types of overlap splice failure. Shear fracture of the impregnation resin within the
overlap splice portion is called “overlap splice failure”. Failure of the FRP sheet in parts of the test portion
other than the overlap splice portion is called “base material failure”.
Table 4 — Categories of overlap-splice failure
Code Type of failure
JF Overlap splice failure
SF Base material failure
6.4.3 Overlap-splice strength
Calculate the overlap-splice strength, f , expressed in newtons per square millimetre and rounded off
fus
to three significant digits, using Formula (6) in accordance with ISO 31-0:1992, Annex B:
F
u
f = (6)
fus
A
where
F is the tensile capacity, expressed in newtons;
u
A is the nominal cross-sectional area, expressed in square millimetres, using Formula (7).
ρ
S −3
Ab=×· 10 (7)
t,min
ρ
sh
where
ρ is the fibre mass per unit area of dry sheet, expressed in grams per square metres;
S
ρ is the density of dry sheet, expressed in grams per cubic centimetres;
sh
b is the minimum width of test portion of the test piece, expressed in millimetres.
t,min
6.5 Test report
The test report shall include the following:
a) name of FRP sheet, date of manufacture, lot number of production run, and name of manufacturer;
b) type of FRP sheet and impregnation resin;
c) fibre mass per unit area of dry sheet and density of dry sheet;
d) fabrication date, fabrication method, and curing conditions (including temperature and duration)
for test pieces;
e) temperature, humidity, and duration of test piece conditioning;
f) test date, test temperature, and loading rate;
g) dimensions of each test piece and calculated cross-sectional area;
h) length of overlap splice for each test piece;
i) tensile capacity of each test piece and average and, if required, standard deviation for these values;
j) tensile strength of each test piece and average and, if required, standard deviation for these values;
k) failure type for each test piece.
7 Test method for determining bond properties of FRP sheets to concrete
7.1 Test pieces
7.1.1 Types and dimensions
a) Type A test pieces: Type A test pieces shall consist of two separate concrete blocks manufactured in
accordance with the method described in 7.1.4.2 a). The shape and the dimensions of a type A test
specimen are shown in Figure 6 and Table 5, respectively.
b) Type B test pieces: Type B test pieces shall consist of a single concrete block manufactured in
accordance with the method described in 7.1.4.2 b). The shape and the dimensions of a type B test
specimen are shown in Figure 7 and Table 5, respectively.
16 © ISO 2015 – All rights reserved

Dimensions in millimetres
b
≥ 200
≥ 200
a
≥ 300
≥ 300
Key
1 anchoring block
2 tensile load
3 separation-type film
4 test block
5 FRP sheet
6 abutted surface
7 anchoring sheet
a
Beveled.
b
Bond length.
Figure 6 — Shape of a type A test piece
Table 5 — Dimensions of test pieces
Dimensions in millimetres
Type of test piece
Element
Type A (separate block type) Type B (single block type)
Length of block ≥300 ≥600
Cross-sectional area of
100 × 100
the block
a
Bond length
...