ISO 19044:2016
(Main)Test methods for fibre-reinforced cementitious composites — Load-displacement curve using notched specimen
Test methods for fibre-reinforced cementitious composites — Load-displacement curve using notched specimen
ISO 19044:2016 specifies the test method for the load-displacement curves of fibre-reinforced cementitious composites (FRCC) by three-point loading of notched prisms. The main purpose of this test is to evaluate the tension softening curve of FRCC.
Méthodes d'essai des composites à base de ciment renforcés par des fibres — Courbe de déplacement de charge utilisant un échantillon entaillé
General Information
Relations
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 19044
First edition
2016-11-01
Test methods for fibre-reinforced
cementitious composites — Load-
displacement curve using notched
specimen
Méthodes d’essai des composites à base de ciment renforcés par des
fibres — Courbe de déplacement de charge utilisant un échantillon
entaillé
Reference number
©
ISO 2016
© ISO 2016, 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 2016 – All rights reserved
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 Test specimen . 2
5.1 Geometry . 2
5.2 Fabrication of specimen . 2
5.3 Loading of specimen . 3
6 Test equipment. 3
6.1 Testing machine . 3
6.2 Loading apparatus . 3
6.3 Measuring device for load . 4
6.4 Measuring device for CMOD . 4
6.5 Measuring device for LPD . 5
7 Test procedure . 5
8 Calculations. 6
9 Test report . 6
Annex A (informative) Method of estimating tension softening curve . 7
Bibliography .10
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 World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
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.
iv © ISO 2016 – All rights reserved
INTERNATIONAL STANDARD ISO 19044:2016(E)
Test methods for fibre-reinforced cementitious
composites — Load-displacement curve using notched
specimen
1 Scope
This document specifies the test method for the load-displacement curves of fibre-reinforced
cementitious composites (FRCC) by three-point loading of notched prisms. The main purpose of this
test is to evaluate the tension softening curve of FRCC.
NOTE 1 Both crack mouth opening displacement (CMOD) and load point displacement (LPD) are specified as
the displacement in load-displacement curves, but measurement of both might not be necessary. Either can be
selected depending on the purpose of measurement.
NOTE 2 Three-point bending test using notched specimen generally provides higher results than those
observed in four-point bending test, in which the fracture occurs at the weakest point of the specimen.
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.
ISO 1920-3:2004, Testing of concrete — Part 3: Making and curing test specimens
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
fibre-reinforced cementitious composite
FRCC
concrete or mortar containing short discrete fibres that are distributed in matrix
Note 1 to entry: Fibres include chemical fibres (metallic fibres, inorganic fibres, synthetic fibres, and so on) and
natural fibres.
3.2
ligament
area above the notch subject to fracture
3.3
notch
cut for the initiation of fracture
4 Symbols
Symbol Unit Description Reference
a mm depth of notch 5.1
b mm width of ligament 5.1
D mm depth of cross section of specimen 5.1
h mm height of ligament 5.1
L mm overall length of specimen 5.1
n mm width of notch 5.1
S mm loading span 5.1
5 Test specimen
5.1 Geometry
Specimens shall be prisms of square cross section with a notch at the mid-length as shown in Figure 1.
a) The cross sectional size of the specimen shall be fixed with two types for the ease of operating
as follows: 150 mm × 150 mm and 100 mm × 100 mm. The side length of the cross section of the
specimen shall be equal to or larger than three times the fibre length.
The specimens with different dimensions provide different test results even if the same FRCC is
used. These test results should not be compared.
b) The overall length of the specimen (L) shall not be less than 3,5 D.
c) The notch depth (a ) and notch width (n ) shall be 0,3 D and not more than 5 mm, respectively.
0 0
D
a
h
n
L
b
Key
1 direction of casting
Figure 1 — Specimen
5.2 Fabrication of specimen
a) The maximum aggregate size shall not be larger than 1/4 of the side length of the cross section of
the specimen.
b) Moulds specified in ISO 1920-3:2004, 5.2.1 shall be used.
2 © ISO 2016 – All rights reserved
c) FRCC shall be placed in one placing sequence without joints. In case of flowable FRCC, pouring
toward the axial direction from the one side of the mould is recommended. The internal vibrator
and compacting rod/bar shall not be used.
d) The notch shall be cut using a concrete saw when the FRCC has developed sufficient strength.
The notch should be cut in one side that faced the side of the mould. The casting surface becomes
vertical one for loading. It is not necessary to cut the edges of the notch to specific forms, as the
edge shape scarcely affects the test results.
e) The number of specimens shall be not less than six. The tolerances of specimens are ±0,5 % for a
side of section.
f) The mass of each specimen shall be measured to the nearest 0,05 kg.
5.3 Loading of specimen
a) Specimens shall be subjected to testing in a condition immediately after completion of the specified
curing procedure.
b) The direction of loading shall be perpendicular to the direction of casting of the specimen.
c) The loading span (S) shall be 3 D. The tolerance of the loading span is ±2 %.
6 Test equipment
6.1 Testing machine
A testing machine capable of operating in a controlled manner, i.e. producing a constant rate of
displacement (CMOD or LPD), and with sufficient stiffness shall be used.
6.2 Loading apparatus
In order to eliminate torsional action on the specimen, the loading block and one of the supports shall
be rotatable around their axes in the direction of the specimen axis. Both supports shall be hinged with
rollers in order to avoid any restraint on the deformation until the specimen completely ruptures.
Both supports should be movable, as the horizontal movement of the specimen is restrained at the
loading block. Inserting multiple rods under both supports as shown in Figure 2 is a simple and effective
solution for a movable mechanism. In order to ensure the absence of horizontal restraint, it is advisable
to press the specimen lightly by hand before applying any load to confirm smooth movement of the
specimen in the horizontal direction.
Key
1 machine head
2 load cell
3 round bar
4 specimen
5 roller
6 round bar ϕ = 20 mm – 30 mm
Figure 2 — Loading apparatus
6.3 Measuring device for load
The load shall be measured using a load cell with an accuracy of 1 % of the estimated peak load or
better. The load cell shall be fixed to the testing machine.
6.4 Measuring device for CMOD
The CMOD shall be measured using a clip gauge with an accuracy of 1/500 mm or better. If clip gauges
cannot be directly attached to the notch, knife-edges are used. The thickness of the knife-edges to which
the clip gauge is attached shall be not more than 5 mm (Figure 3). If the knife-edges are used, measuring
position of CMOD shall be indicated in the test report. Also, if the inverse analysis is conducted, the
measuring position should be considered.
Knife-edges, which should be made of metal, should be attached as shown in Figure 3 using an adhesive
to ensure bond with the specimen. When wet testing is to be conducted with knife-edges attached to
the specimen with an adhesive, the surfaces receiving the knife-edges have to be temporarily dried at
the time of adhering. In this case, it is advisable that the portions other than the surfaces receiving the
knife-edges be covered with a wet cloth or immersed in water to avoid drying.
≦5 mm
Figure 3 — Knife-edges
4 © ISO 2016 – All rights reserved
6.5 Measuring device for LPD
The LPD shall be measured using displacement transducers as shown in Figure 4. The transducers shall
have an accuracy of 1/500 mm or better. Holder frames, made of aluminium or steel bars, shall be used
in order to eliminate the rigid-body
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.