SIST EN 12697-26:2018
(Main)Bituminous mixtures - Test methods - Part 26: Stiffness
Bituminous mixtures - Test methods - Part 26: Stiffness
This European Standard specifies the methods for characterising the stiffness of bituminous mixtures by alternative tests, including bending tests and direct and indirect tensile tests. The tests are performed on compacted bituminous material under a sinusoidal loading or other controlled loading, using different types of specimens and supports.
The procedure is used to rank bituminous mixtures on the basis of stiffness, as a guide to relative performance in the pavement, to obtain data for estimating the structural behaviour in the road and to judge test data according to specifications for bituminous mixtures.
As this standard does not impose a particular type of testing device the precise choice of the test conditions depends on the possibilities and the working range of the used device.
For the choice of specific test conditions, the requirements of the product standards for bituminous mixtures should be respected.
The applicability of this document is described in the product standards for bituminous mixtures.
Asphalt - Prüfverfahren - Teil 26: Steifigkeit
Diese Europäische Norm legt die Verfahren zur Charakterisierung der Steifigkeit von Asphalt durch verschiedene Prüfungen, einschließlich Biegeprüfungen sowie direkte und indirekte Zugprüfungen, fest. Die Prüfungen werden an verdichtetem Asphalt unter sinusförmiger oder einer anderen kontrollierten Belastung unter Verwendung verschiedener Probekörpertypen und Auflagerungen vorgenommen.
Das Verfahren dient zur Einstufung von Asphalt auf der Grundlage seiner Steifigkeit als Hinweis auf das relative Leistungsvermögen von Asphalt in der Fahrbahnbefestigung, um Daten zur Abschätzung des Tragverhaltens in der Straße zu erhalten und um die Prüfdaten nach den für Asphalt geltenden Festlegungen zu beurteilen.
Da diese Norm keinen bestimmten Prüfgerätetyp vorschreibt, hängt die genaue Auswahl der Prüfbedingungen vom Einsatz- und Arbeitsbereich des verwendeten Prüfgeräts ab.
Bei der Auswahl der jeweiligen Prüfbedingungen sollten die Anforderungen der Produktnormen für Asphalt berücksichtigt werden.
Die Anwendbarkeit dieses Dokumentes ist in den Produktnormen für Asphalt beschrieben.
Mélanges bitumineux - Méthodes d'essai pour enrobés à chaud - Partie 26 : Rigidité
La présente Norme européenne spécifie les méthodes de caractérisation de la rigidité des mélanges bitumineux à l'aide d'essais au choix, comprenant des essais de flexion et des essais de traction directe et indirecte. Les essais sont réalisés sur des matériaux bitumineux compactés, au moyen d'un chargement sinusoïdal ou d'un autre chargement contrôlé, en utilisant différents types d'éprouvettes et de supports.
La procédure est utilisée pour classer les mélanges bitumineux en fonction de leur rigidité, pour servir de guide pour les performances relatives dans les chaussées, pour disposer de données utilisées pour estimer le comportement structurel dans les chaussées et juger les résultats d'essais en fonction des spécifications concernant les mélanges bitumineux.
La présente norme n'imposant pas de type particulier d'appareillage d'essai, le choix spécifique des conditions d'essai dépend des capacités et du domaine d'emploi de l'appareillage utilisé.
Pour le choix des conditions d'essai spécifiques, il convient de respecter les exigences des normes produit sur les mélanges bitumineux.
L'applicabilité du présent document est décrite dans les normes produit des mélanges bitumineux.
Bitumenske zmesi - Preskusne metode - 26. del: Togost
Ta evropski standard določa metode za karakterizacijo togosti bitumenskih zmesi z alternativnimi preskusi, skupaj s preskusi upogiba in preskusi direktne ter indirektne nateznosti. Preskusi se izvajajo na zgoščenem bitumenskem materialu pod sinusnim obremenjevanjem ali pod nadzorovanim obremenjevanjem z različnimi vrstami preskušancev in podpor.
Postopek se uporablja za razvrščanje bitumenskih zmesi na podlagi togosti kot smernica v zvezi z relativnimi lastnostmi v voziščni konstrukciji za pridobivanje podatkov z namenom vrednotenja strukturnega obnašanja na cesti ter za ocenjevanje preskusnih podatkov glede na specifikacije bitumenskih zmesi.
Ker ta standard ne predpisuje posebne preskusne naprave, je natančna izbira preskusnih pogojev odvisna od možnosti in delovnega obsega uporabljene naprave.
Pri izbiri specifičnih preskusnih pogojev je treba upoštevati standarde za izdelke za bitumenske zmesi.
Uporabnost tega dokumenta je opisana v standardih za izdelke za bitumenske zmesi.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 12697-26:2018
01-september-2018
1DGRPHãþD
SIST EN 12697-26:2012
Bitumenske zmesi - Preskusne metode - 26. del: Togost
Bituminous mixtures - Test methods - Part 26: Stiffness
Asphalt - Prüfverfahren - Teil 26: Steifigkeit
Mélanges bitumineux - Méthodes d'essai pour enrobés à chaud - Partie 26 : Rigidité
Ta slovenski standard je istoveten z: EN 12697-26:2018
ICS:
93.080.20 Materiali za gradnjo cest Road construction materials
SIST EN 12697-26:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 12697-26:2018
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SIST EN 12697-26:2018
EN 12697-26
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2018
EUROPÄISCHE NORM
ICS 93.080.20 Supersedes EN 12697-26:2012
English Version
Bituminous mixtures - Test methods - Part 26: Stiffness
Mélanges bitumineux - Méthodes d'essai - Partie 26: Asphalt - Prüfverfahren - Teil 26: Steifigkeit
Module de rigidité
This European Standard was approved by CEN on 26 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 12697-26:2018 E
worldwide for CEN national Members.
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SIST EN 12697-26:2018
EN 12697-26:2018 (E)
Contents Page
European foreword . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and symbols . 6
3.1 Terms and definitions . 6
3.2 Symbols . 8
4 Principle . 9
5 Sample preparation . 9
5.1 Age of the specimens . 9
5.2 Drying of the specimens . 9
5.3 Dimensions and bulk density of the specimens . 9
5.4 Number of test specimens . 10
6 Checking of the testing equipment . 10
7 Test methods . 10
7.1 General . 10
7.2 Codification of tests . 10
7.2.1 Sinusoidal bending tests . 10
7.2.2 lndirect tensile test (pulse or cyclic) . 11
7.2.3 Cyclic or monotonous uniaxial tests . 11
7.2.4 Loading conditions . 11
7.2.5 Load amplitudes . 11
7.2.6 Loading frequencies . 11
7.3 Controlled strain rate loading . 12
7.3.1 Test method . 12
7.3.2 Loading conditions . 12
7.3.3 Strain amplitudes for direct tensile tests . 12
8 Temperatures . 13
9 Expression of results . 13
10 Test report . 15
10.1 Introduction . 15
10.2 General . 15
10.3 Information on specimens . 15
10.4 Information on test method . 15
10.5 Information on the test and results . 16
10.6 Optional information . 16
11 Precision . 16
Annex A (normative) Two point bending test on trapezoidal specimens (2PB-TR) or on
prismatic specimens (2PB-PR) . 17
A.1 Principle . 17
A.2 Equipment . 17
A.3 Specimen preparation . 19
2
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EN 12697-26:2018 (E)
A.4 Procedure . 20
Annex B (normative) Three point bending test on prismatic specimens (3PB-PR) and four
point bending test on prismatic specimens (4PB-PR). 21
B.1 Principle . 21
B.2 Equipment . 22
B.3 Specimen preparation . 23
B.3.1 Dimensions . 23
B.3.2 Sample manufacture . 23
B.4 Procedure . 24
Annex C (normative) Test applying indirect tension to cylindrical specimens (IT-CY) . 25
C.1 Principle . 25
C.2 Equipment . 25
C.2.1 General devices . 25
C.2.2 Test equipment . 25
C.3 Specimen preparation . 30
C.4 Mode of operation . 31
C.4.1 Mounting the specimen . 31
C.4.2 Stiffness measurement . 31
Annex D (normative) Direct tension-compression test on cylindrical specimens (DTC-CY) . 33
D.1 Principle . 33
D.2 Equipment . 33
D.3 Specimen preparation . 33
D.4 Mode of operation . 35
D.4.1 Stabilizing the specimen . 35
D.4.2 Procedure . 35
Annex E (normative) Test applying direct tension to cylindrical specimens (DT-CY) or to
prismatic specimens (DT-PR) . 36
E.1 Principle . 36
E.2 Equipment . 36
E.3 Specimen preparation . 36
E.3.1 Cylindrical specimen . 36
E.3.2 Prismatic specimen . 37
E.4 Mode of operation . 37
E.4.1 Stabilization of the specimen . 37
E.4.2 Procedure . 38
E.5 Derivation of the master-curve - Isotherms . 39
Annex F (normative) Test applying cyclic indirect tension to cylindrical specimens (CIT-CY) . 40
3
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EN 12697-26:2018 (E)
F.1 Principle . 40
F.2 Equipment . 40
F.2.1 Test machine . 40
F.2.2 Loading. 40
F.2.3 Displacement . 40
F.2.4 Thermostatic chamber . 42
F.2.5 Recording and measuring system . 42
F.2.6 Loading strips . 42
F.3 Specimen preparation . 42
F.3.1 Test specimen . 42
F.3.2 Specimen dimensions . 43
F.4 Mode of operation . 43
F.4.1 Test temperature . 43
F.4.2 Mounting the specimen . 43
F.4.3 Procedure. 43
F.4.4 Checking of specimen deterioration . 44
Annex G (informative) Derivation of the master curve . 45
G.1 Principle . 45
G.2 Theoretical background . 46
G.3 Experimental data. 47
G.4 Test report . 48
4
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SIST EN 12697-26:2018
EN 12697-26:2018 (E)
European foreword
This document (EN 12697-26:2018) has been prepared by Technical Committee CEN/TC 227 “Road
materials”, 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 December 2018, and conflicting national standards
shall be withdrawn at the latest by December 2018.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN not be held responsible for identifying any or all such patent rights.
This document supersedes EN 12697-26:2012.
Compared with EN 12697-26:2012, the following changes have been made:
— the series title no longer makes the method exclusively for hot mix asphalt [Title];
— implementation of a real haversinusoidal load in Annex C;
— implementation of several technical corrections in all annexes;
— adjustment of procedures in all the tests;
— application of the correct wording within all the test procedures.
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.
5
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SIST EN 12697-26:2018
EN 12697-26:2018 (E)
1 Scope
This European Standard specifies the methods for characterizing the stiffness of bituminous mixtures
by alternative tests, including bending tests and direct and indirect tensile tests. The tests are
performed on compacted bituminous material under a sinusoidal loading or other controlled loading,
using different types of specimens and supports.
The procedure is used to rank bituminous mixtures on the basis of stiffness, as a guide to relative
performance in the pavement, to obtain data for estimating the structural behaviour in the road and to
judge test data according to specifications for bituminous mixtures.
As this standard does not impose a particular type of testing device the precise choice of the test
conditions depends on the operating scope and working range of the device used.
For the choice of specific test conditions, the requirements of the product standards for bituminous
mixtures should be respected.
The applicability of this document is described in the product standards for bituminous mixtures.
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.
EN 12697-6, Bituminous mixtures — Test methods for hot mix asphalt — Part 6: Determination of bulk
density of bituminous specimens
EN 12697-7, Bituminous mixtures — Test methods for hot mix asphalt — Part 7: Determination of bulk
density of bituminous specimens by gamma rays
EN 12697-27, Bituminous mixtures — Test methods — Part 27: Sampling
EN 12697-29, Bituminous mixtures — Test method for hot mix asphalt — Part 29: Determination of the
dimensions of a bituminous specimen
EN 12697-31, Bituminous mixtures — Test methods for hot mix asphalt — Part 31: Specimen preparation
by gyratory compactor
EN 12697-33, Bituminous mixtures — Test methods — Part 33: Specimen prepared by roller compactor
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
stiffness modulus
relationship between maximum applied stress and maximum measured strain response and expressed
as:
σ
E = (1)
ε
6
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SIST EN 12697-26:2018
EN 12697-26:2018 (E)
3.1.2
complex modulus
relationship between stress and strain for a linear visco-elastic material submitted to a sinusoidal load
wave form at time, t, where applying a stress σ × sin (ω × t) results in a strain ε × sin (ω × t − Φ) that has
a phase angle, Φ, with respect to the stress
The amplitude of strain and the phase angle are functions of the frequency, f, and the test temperature,
Θ.
The stress strain ratio defines the complex modulus E* as:
EE* * ⋅(cos()Φ+ i⋅sin ()Φ ) (2)
The complex modulus depends on the frequency f and the temperature θ. The complex modulus is
characterised in two ways:
1. By the real component E and the imaginary components E :
1 2
E E* ⋅cos( Φ) (3)
1
EE= *⋅Φsin ( ) (4)
2
2. By the absolute value of the complex modulus ∣E*∣ and the phase angle, Φ:
2 2
E* EE+ (5)
12
E
2
Φ= arctan
(6)
E
1
This second characterization is more often used in practice. In linear elastic multi-layer calculations for
instance the E* modulus is generally used as input value for Young’s modulus.
Note 1 to entry: For purely elastic materials, the phase angle is zero and then the complex modulus reduces to the
Young’s modulus. This happens when bituminous materials are at very low temperatures. Then the complex
modulus reaches its highest possible value, noted E .
∞
7
=
=
=
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EN 12697-26:2018 (E)
3.1.3
secant modulus
relationship between stress and strain at the loading time, t, for a material subjected to controlled
loading (force or displacement):
σ ()t
E(t) = (7)
ε (t)
with stress, σ(t), and strain, ε(t), at time t
Note 1 to entry: The strain law is
n
ε ()ttα ⋅
(8)
i
where α and n are constants.
i
Note 2 to entry: Several successive tests can be carried out on the same specimen for different values of α . For
i
linear visco-elastic materials, the secant modulus obtained for different values of α at the same temperature
i
depends on the loading time, t, only.
3.2 Symbols
For the purposes of this document, the following symbols apply:
D maximum aggregate size in an asphalt mix in millimetre (mm);
E the elastic stiffness (modulus), in megapascals (MPa);
E* the visco-elastic complex modulus, in megapascals (MPa);
|E*| absolute modulus of the complex modulus, in megapascals (MPa);
E the real component of the complex modulus, in megapascals (MPa);
1
E the imaginary component of the complex modulus, in megapascals (MPa);
2
E the highest possible value of the complex modulus, in megapascals (MPa);
∞
F the loading force, in newtons (N);
h the mean thickness of the specimen, in millimetres (mm);
H the height of a cylindrical specimen, in millimetres (mm);
l the original length of the measurement area in millimetres (mm);
0
Δl the elongation of the measurement area in micrometers (µm);
L the span length between outer supports in bending tests, in millimetres (mm);
m mass of the movable parts in grams (g);
M weight of the sample in grams (g);
t the loading time, in seconds (s);
Θ the test temperature, in degrees celsius (°C);
z the displacement, in millimetres (mm);
8
=
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EN 12697-26:2018 (E)
f the test frequency in Hertz (Hz);
σ the applied stress, in megapascals (MPa);
ε the applied strain, in micrometer per meter or in microstrain (µm/m);
ε the maximum strain applied to the test specimen, in micrometer per meter or in microstrain
max
(μm/m);
ω the angular speed, in radians per second (rad/s);
φ the phase shift between the force and the displacement in degrees (°);
Φ the modulus phase angle of the material (argument), in degrees (°);
γ −1
the form factor which is a function of specimen size and form (1/mm or mm );
μ the mass factor which is a function of the mass of the specimen and the mass of the movable
parts that influence the resultant force by their inertial effects in grams (g);
ν the Poisson’s ratio;
∅ the diameter of a cylindrical specimen, in millimetres (mm).
4 Principle
Suitable shaped samples are deformed in their linear range, under repeated loads or controlled strain
rate loads. From the measured force and deformation signal, amplitudes of the stress and strain, and the
phase angle between both are calculated. Based on measured stress and strain desired moduli can be
calculated.
5 Sample preparation
5.1 Age of the specimens
Prior to the start of testing, the specimens shall be stored on a flat surface at a temperature of not more
than 20 °C for between 14 d and 42 d from the time of their manufacture. In the case of samples
requiring cutting and/or gluing, the cutting shall be performed no more than 8 d after compaction of the
asphalt and the gluing shall be performed at least 2 weeks from cutting. The time of manufacture for
these samples is the time when they are cut.
NOTE 1 The storage time influences the mechanical properties of the specimen.
NOTE 2 For test purposes other than for CE marking, different storage times can be applied.
5.2 Drying of the specimens
After sawing and before gluing and/or testing, the specimens shall be dried to constant mass in air at a
relative air humidity of less than 80 % at a temperature not more than 20 °C. A test specimen shall be
considered to be dry after at least 8 h drying time and when two weighings performed minimum 4 h
apart differ by less than 0,1 %.
5.3 Dimensions and bulk density of the specimens
The dimensions of the specimens shall be measured according to EN 12697-29.
The bulk density shall be determined in accordance with EN 12697-6 or EN 12697-7. The bulk density
of each specimen shall not differ by more than 1 % from the average density of the batch. Otherwise, the
specimen shall be rejected.
9
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EN 12697-26:2018 (E)
5.4 Number of test specimens
For all test methods described in this standard, the stiffness modulus of a minimum of 4 specimens shall
be tested. The average of these results determine the stiffness modulus for the tested mix.
6 Checking of the testing equipment
The completely assembled testing equipment shall be checked periodically with at least one reference
specimen with a known stiffness modulus (modulus and phase lag). To check the test equipment for
Annexes A and B, the bending moment (E.I) of the specimen(s) shall be chosen to be equal to the
bending moment of a normal asphalt test specimen (adopting a stiffness modulus for the asphalt in the
range of 3 GPa to 14 GPa); for Annexes C, D, E and F an appropriate checking specimen with a known
stiffness between 3 GPa and 14 GPa shall be used.
The checking should be applied for each applied test temperature. For cyclic tests (Annex A, B, D, and F)
the reference specimen shall be tested at not less than 6 frequencies and 2 deformation levels. For
impulsive tests (Annex C), the reference specimen shall be submitted to a minimum of 4 trials in regular
test conditions. For monotonic tests (Annex E), the reference specimen sha
...
SLOVENSKI STANDARD
oSIST prEN 12697-26:2016
01-januar-2016
Bitumenske zmesi - Preskusne metode - 26. del: Togost
Bituminous mixtures - Test methods - Part 26: Stiffness
Asphalt - Prüfverfahren - Teil 26: Steifigkeit
Mélanges bitumineux - Méthodes d'essai pour enrobés à chaud - Partie 26 : Rigidité
Ta slovenski standard je istoveten z: prEN 12697-26
ICS:
93.080.20 Materiali za gradnjo cest Road construction materials
oSIST prEN 12697-26:2016 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 12697-26:2016
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oSIST prEN 12697-26:2016
DRAFT
EUROPEAN STANDARD
prEN 12697-26
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2015
ICS 93.080.20 Will supersede EN 12697-26:2012
English Version
Bituminous mixtures - Test methods - Part 26: Stiffness
Mélanges bitumineux - Méthodes d'essai pour enrobés Asphalt - Prüfverfahren - Teil 26: Steifigkeit
à chaud - Partie 26 : Rigidité
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 227.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12697-26:2015 E
worldwide for CEN national Members.
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oSIST prEN 12697-26:2016
prEN 12697-26:2015 (E)
Contents Page
European foreword . 5
1 Scope . 9
2 Normative references . 9
3 Terms, definitions and symbols . 10
3.1 Terms and definitions . 10
3.2 Symbols . 11
4 Principle . 12
5 Sample preparation . 12
5.1 Age of the specimens . 12
5.2 Drying of the specimen . 12
5.3 Dimensions and bulk density of the specimens . 12
5.4 Number of test specimens . 12
6 Checking of the testing equipment . 12
7 Test methods . 13
7.1 General . 13
7.2 Tests with sinusoidal or pulse loading . 13
7.2.1 Bending tests . 13
7.2.2 lndirect tensile test . 13
7.2.3 Direct uniaxial tests . 14
7.2.4 Loading conditions . 14
7.2.5 Load amplitudes . 14
7.2.6 Loading frequencies . 14
7.3 Controlled strain rate loading . 15
7.3.1 Test method . 15
7.3.2 Loading conditions . 15
7.3.3 Strain amplitudes . 15
8 Temperatures . 16
9 Expression of results . 16
10 Test report . 18
10.1 General . 18
10.2 Information on specimen . 18
10.3 Information on test method . 18
10.4 Information on the test and results . 19
10.5 Optional information . 19
11 Precision . 19
Annex A (normative) Two point bending test on trapezoidal specimens (2PB-TR) or on
prismatic specimens (2PB-PR) . 20
A.1 Principle . 20
A.2 Equipment . 20
2
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prEN 12697-26:2015 (E)
A.3 Specimen preparation . 22
A.4 Procedure . 23
Annex B (normative) Three point bending test on prismatic specimens (3PB-PR) and four
point bending test on prismatic specimens (4PB-PR). 24
B.1 Principle . 24
B.2 Equipment . 25
B.3 Specimen preparation . 27
B.3.1 Dimensions . 27
B.3.2 Sample manufacture . 27
B.4 Procedure . 27
Annex C (normative) Test applying indirect tension to cylindrical specimens (IT-CY) . 29
C.1 Principle . 29
C.2 Equipment . 29
C.2.1 General devices . 29
C.2.2 Test equipment . 29
C.3 Specimen preparation . 34
C.4 Mode of operation . 35
C.4.1 Mounting the specimen . 35
C.4.2 Stiffness measurement . 35
C.4.2.1 Conditioning load pulses . 35
C.4.2.2 Deformation measuring . 35
C.4.2.3 Calculation of the measured stiffness modulus . 35
C.4.2.4 Stiffness modulus of the specimen . 36
Annex D (normative) Direct tension-compression test on cylindrical specimens (DTC-CY) . 37
D.1 Principle . 37
D.2 Equipment . 37
D.3 Specimen preparation . 37
D.4 Mode of operation . 39
D.4.1 Stabilizing the specimen . 39
D.4.2 Procedure . 39
Annex E (normative) Test applying direct tension to cylindrical specimens (DT-CY) or to
prismatic specimens (DT-PR) . 40
E.1 Principle . 40
E.2 Equipment . 40
E.3 Specimen preparation . 40
E.3.1 Cylindrical specimen . 40
E.3.2 Prismatic specimen . 41
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E.4 Mode of operation . 41
E.4.1 Stabilization of the specimen . 41
E.4.1.1 Temperature stabilization . 41
E.4.1.3 Mechanical stabilization between tests . 42
E.4.2 Procedure. 42
E.5 Derivation of the master-curve . 43
E.5.1 Isotherms . 43
E.5.2 Master curve at a fixed temperature . 44
E.6 Determination of the stiffness modulus for the fixed loading time . 45
Annex F (normative) Test applying Cyclic indirect tension to cylindrical specimens (CIT-
CY) . 47
F.1 Principle . 47
F.2 Equipment . 47
F.2.1 Test machine . 47
F.2.2 Loading. 47
F.2.3 Displacement . 47
F.2.4 Thermostatic chamber . 49
F.2.5 Recording and measuring system . 49
F.2.6 Loading strips . 49
F.3 Specimen preparation . 49
F.3.1 Test specimen . 49
F.3.2 Specimen dimensions . 50
F.4 Mode of operation . 50
F.4.1 Test temperature . 50
F.4.2 Mounting the specimen . 50
F.4.3 Procedure. 50
F.4.3.1 General . 50
F.4.3.2 Load frequency . 51
F.4.3.3 Definition of the lower load level . 51
F.4.3.4 Definition of the upper load level. 51
F.4.4 Checking of specimen deterioration . 51
Annex G (informative) Derivation of the master curve . 52
G.1 Principle . 52
G.2 Theoretical background . 53
G.3 Experimental data. 54
G.4 Test report . 55
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prEN 12697-26:2015 (E)
European foreword
This document (prEN 12697-26:2015) has been prepared by Technical Committee CEN/TC 227 “Road
materials”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12697-26:2012.
This document is one of a series of standards as listed below:
— EN 12697-1, Bituminous mixtures — Test methods for hot mix asphalt — Part 1: Soluble binder
content
— EN 12697-2, Bituminous mixtures — Test methods for hot mix asphalt — Part 2: Determination of
particle size distribution
— EN 12697-3, Bituminous mixtures — Test methods for hot mix asphalt — Part 3: Bitumen recovery:
Rotary evaporator
— EN 12697-4, Bituminous mixtures — Test methods for hot mix asphalt — Part 4: Bitumen recovery:
Fractionating column
— EN 12697-5, Bituminous mixtures — Test methods for hot mix asphalt — Part 5: Determination of the
maximum density
— EN 12697-6, Bituminous mixtures — Test methods for hot mix asphalt — Part 6: Determination of
bulk density of bituminous specimens
— EN 12697-7, Bituminous mixtures — Test methods for hot mix asphalt — Part 7: Determination of
bulk density of bituminous specimens by gamma rays
— EN 12697-8, Bituminous mixtures — Test methods for hot mix asphalt — Part 8: Determination of
void characteristics of bituminous specimens
— EN 12697-10, Bituminous mixtures — Test methods for hot mix asphalt — Part 10: Compactability
— EN 12697-11, Bituminous mixtures — Test methods for hot mix asphalt — Part 11: Determination of
the affinity between aggregate and bitumen
— EN 12697-12, Bituminous mixtures — Test methods for hot mix asphalt — Part 12: Determination of
the water sensitivity of bituminous specimens
— EN 12697-13, Bituminous mixtures — Test methods for hot mix asphalt — Part 13: Temperature
measurement
— EN 12697-14, Bituminous mixtures — Test methods for hot mix asphalt — Part 14: Water content
— EN 12697-15, Bituminous mixtures — Test methods for hot mix asphalt — Part 15: Determination of
the segregation sensitivity
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oSIST prEN 12697-26:2016
prEN 12697-26:2015 (E)
— EN 12697-16, Bituminous mixtures — Test methods for hot mix asphalt — Part 16: Abrasion by
studded tyres
— EN 12697-17, Bituminous mixtures — Test methods for hot mix asphalt — Part 17: Particle loss of
porous asphalt specimen
1)
— EN 12697-18, Bituminous mixtures — Test methods — Part 18: Binder drainage
— EN 12697-19, Bituminous mixtures — Test methods for hot mix asphalt — Part 19: Permeability of
specimen
— EN 12697-20, Bituminous mixtures — Test methods for hot mix asphalt — Part 20: Indentation using
cube or cylindrical specimens (CY)
— EN 12697-21, Bituminous mixtures — Test methods for hot mix asphalt — Part 21: Indentation using
plate specimens
— EN 12697-22, Bituminous mixtures — Test methods for hot mix asphalt — Part 22: Wheel tracking
— EN 12697-23, Bituminous mixtures — Test methods for hot mix asphalt — Part 23: Determination of
the indirect tensile strength of bituminous specimens
1)
— EN 12697-24, Bituminous mixtures — Test methods — Part 24: Resistance to fatigue
— EN 12697-25, Bituminous mixtures — Test methods for hot mix asphalt — Part 25: Cyclic
compression test
1)
— EN 12697-26, Bituminous mixtures — Test methods — Part 26: Stiffness
— EN 12697-27, Bituminous mixtures — Test methods for hot mix asphalt — Part 27: Sampling
— EN 12697-28, Bituminous mixtures — Test methods for hot mix asphalt — Part 28: Preparation of
samples for determining binder content, water content and grading
— EN 12697-29, Bituminous mixtures — Test methods for hot mix asphalt — Part 29: Determination of
the dimensions of a bituminous specimen
— EN 12697-30, Bituminous mixtures — Test methods for hot mix asphalt — Part 30: Specimen
preparation by impact compactor
— EN 12697-31, Bituminous mixtures — Test methods for hot mix asphalt — Part 31: Specimen
preparation by gyratory compactor
— EN 12697-32, Bituminous mixtures — Test methods for hot mix asphalt — Part 32: Laboratory
compaction of bituminous specimens by vibratory compactor
— EN 12697-33, Bituminous mixtures — Test methods for hot mix asphalt — Part 33: Specimen
prepared by roller compactor
— EN 12697-34, Bituminous mixtures — Test methods for hot mix asphalt — Part 34: Marshall test
1)
In preparation
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oSIST prEN 12697-26:2016
prEN 12697-26:2015 (E)
— EN 12697-35, Bituminous mixtures — Test methods for hot mix asphalt — Part 35: Laboratory
mixing
— EN 12697-36, Bituminous mixtures — Test methods for hot mix asphalt — Part 36: Determination of
the thickness of a bituminous pavement
— EN 12697-37, Bituminous mixtures — Test methods for hot mix asphalt — Part 37: Hot sand test for
the adhesivity of binder on precoated chippings for HRA
— EN 12697-38, Bituminous mixtures — Test methods for hot mix asphalt — Part 38: Common
equipment and calibration
— EN 12697-39, Bituminous mixtures — Test methods for hot mix asphalt — Part 39: Binder content by
ignition
— EN 12697-40, Bituminous mixtures — Test methods for hot mix asphalt — Part 40: In situ
drainability
— EN 12697-41, Bituminous mixtures — Test methods for hot mix asphalt — Part 41: Resistance to de-
icing fluids
— EN 12697-42, Bituminous mixtures — Test methods for hot mix asphalt — Part 42: Amount of foreign
matters in reclaimed asphalt
— EN 12697-43, Bituminous mixtures — Test methods for hot mix asphalt — Part 43: Resistance to fuel
— EN 12697-44, Bituminous mixtures — Test methods for hot mix asphalt — Part 44: Crack
propagation by semi-circular bending test
— EN 12697-45, Bituminous mixtures — Test methods for hot mix asphalt — Part 45: Saturation ageing
tensile stiffness (SATS) conditioning test
— EN 12697-46, Bituminous mixtures — Test methods for hot mix asphalt — Part 46: Low temperature
cracking and properties by uniaxial tension tests
— EN 12697-47, Bituminous mixtures — Test methods for hot mix asphalt — Part 47: Determination of
the ash content of natural asphalts
1)
— EN 12697-48, Bituminous mixtures — Test methods — Part 48: Interlayer bonding
— EN 12697-49, Bituminous mixtures — Test methods for hot mix asphalt — Part 49: Determination of
friction after polishing
1)
— CEN/TS 12697-50, Bituminous mixtures — Test methods — Part 50: Resistance to scuffing
1)
— EN 12697-51, Bituminous mixtures — Test methods — Part 51: Surface shear strength test
— CEN/TS 12697-52, Bituminous mixtures — Test methods — Part 52: Conditioning to address
1)
oxidative ageing
— EN 12697-53, Bituminous mixtures — Test methods — Part 53: Cohesion increase by spreadability-
1)
meter method
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oSIST prEN 12697-26:2016
prEN 12697-26:2015 (E)
Compared with EN 12697-26:2012, the following changes have been made:
a) implementation of a real haversinusoidal load in Annex C;
b) implementation of several technical corrections in all annexes;
c) adjustment of procedures in all the tests;
d) application of the correct wording within all the test procedures.
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1 Scope
This European Standard specifies the methods for characterizing the stiffness of bituminous mixtures
by alternative tests, including bending tests and direct and indirect tensile tests. The tests are
performed on compacted bituminous material under a sinusoidal loading or other controlled loading,
using different types of specimens and supports.
The procedure is used to rank bituminous mixtures on the basis of stiffness, as a guide to relative
performance in the pavement, to obtain data for estimating the structural behaviour in the road and to
judge test data according to specifications for bituminous mixtures.
As this standard does not impose a particular type of testing device the precise choice of the test
conditions depends on the possibilities and the working range of the used device.
For the choice of specific test conditions, the requirements of the product standards for bituminous
mixtures should be respected.
The applicability of this document is described in the product standards for bituminous mixtures.
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.
EN 12697-6, Bituminous mixtures - Test methods for hot mix asphalt - Part 6: Determination of bulk
density of bituminous specimens
EN 12697-7, Bituminous mixtures - Test methods for hot mix asphalt
...
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