ISO 19044:2016

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

• Status: Published
• Publication Date: 30-Oct-2016
• ICS: 83.120 - Reinforced plastics
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: ISO/TC 71/SC 6 - Non-traditional reinforcing materials for concrete structures
• Drafting Committee: ISO/TC 71/SC 6/WG 2 - Testing methods for fibre-reinforced cementitious composites
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 04-Dec-2024
• Completion Date: 13-Dec-2025

Relations

• Consolidated By: ISO 4016:2022 - Fasteners - Hexagon head bolts - Product grade C
• Effective Date: 06-Jun-2022
• Revised: ISO 19044:2024 - Test methods for fibre-reinforced cementitious composites - Load-displacement curve using notched specimen
• Effective Date: 17-Dec-2022

Overview

ISO 19044:2016 specifies a standardized laboratory method to obtain load–displacement curves for fibre‑reinforced cementitious composites (FRCC) using three‑point bending on notched prism specimens. The main aim is to evaluate the tension softening curve - the relationship between crack mouth opening (CMOD) and cohesive stress - which is essential for fracture and post‑crack behaviour analysis of FRCC.

Key topics and requirements

• Specimen geometry and fabrication
  • Prisms with square cross‑section: 100 × 100 mm or 150 × 150 mm; overall length ≥ 3.5D.
  • Notch depth = 0.3 D and notch width ≤ 5 mm.
  • Minimum of six specimens per test series.
  • Maximum aggregate size ≤ 1/4 side length; moulding per ISO 1920‑3; avoid internal vibration/compaction.
• Loading and supports
  • Three‑point bending with loading span S = 3 D (±2%).
  • Supports and loading block designed to avoid torsion and horizontal restraint (rotatable/hinged supports).
• Measurements and accuracy
  • Load cell accuracy: ≤1% of estimated peak load.
  • CMOD or LPD transducers accuracy: ≤1/500 mm.
  • Clip gauges or knife‑edges (≤5 mm) permitted for CMOD; report measuring positions.
• Test procedure
  • Controlled displacement rate: 0.05 mm/min until CMOD/LPD = 0.1 mm, then may increase to 0.2 mm/min.
  • Data acquisition: ≥ 5 Hz during rapid load changes, then ≥ 1 Hz afterwards.
  • Continue test until CMOD ≥ 0.04 D or LPD ≥ 0.03 D (longer desirable for large deformation properties).
• Data processing
  • Average load–displacement curves from at least six specimens.
  • Annex A describes inverse analysis / poly‑linear approximation to estimate the tension softening curve from load–CMOD data.

Applications and users

ISO 19044:2016 is relevant for:

• Materials researchers and academic labs studying FRCC fracture and post‑crack behaviour.
• Concrete and mortar testing laboratories validating fibre types, lengths, and volume fractions.
• Structural engineers and designers using fracture models (fictitious crack model) and finite element analyses that require tension softening inputs.
• Manufacturers of fibre‑reinforced cementitious products who need standardized performance data for quality control and product development.

Practical uses include comparing post‑crack load capacity, deriving cohesive laws for numerical modelling, and supporting specification or certification of FRCC materials.

Related standards

• ISO 1920‑3:2004 - referenced for specimen moulds and curing procedures.
• Use together with standards on concrete testing and material characterization when preparing specimens and reporting results.

Keywords: ISO 19044:2016, FRCC, fibre‑reinforced cementitious composites, load‑displacement curve, notched specimen, tension softening curve, CMOD, LPD, three‑point bending.

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. [phone]
Fax [phone]
[e-mail]
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 s
...