SIST EN 12697-26:2005
(Main)Bituminous mixtures - Test methods for hot mix asphalt - Part 26: Stiffness
Bituminous mixtures - Test methods for hot mix asphalt - Part 26: Stiffness
This document 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 shall be respected.
The applicability of this document is described in the product standards for bituminous mixtures.
Asphalt - Prüfverfahren für Heißasphalt - Teil 26: Steifigkeit
Die vorliegende Norm beschreibt das Verfahren zur Bewertung von Prüfungen, deren Ziel es ist, die Steifigkeitseigenschaften von Asphalt zu kennzeichnen. Solche Prüfungen werden an verdichteten bitumenhaltigen Baustoffen unter einer sinusförmigen oder anderen geregelten Belastung unter Verwendung unterschiedlicher Typen von Probekörpern und Tragwerken ausgeführt. Die anwendbaren Prüfverfahren sind im Abschnitt 5 zusammengestellt.
Mélanges bitumineux - Méthodes d'essai pour mélange hydrocarboné a chaud - Partie 26: Module de rigidité
Le présent document spécifie les méthodes de caractérisation de la rigidité des mélanges hydrocarbonés a l'aide d'essais au choix, comprenant des essais de flexion et des essais de traction directe et indirecte. Les essais sont réalisés sur un matériau bitumineux compacté soumis a une charge sinusoidale ou a d'autres charges contrôlées, utilisant différents types d'éprouvettes et de supports.
La procédure est utilisée pour classer les mélanges hydrocarbonés en fonction de leur module de rigidité, pour servir de guide pour les performances relatives dans les chaussées, pour disposer de données utilisées pour estimer le comportement structurel des chaussées et juger les résultats d'essais en fonction des spécifications concernant les mélanges hydrocarbonés.
Cette 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, les exigences des normes produit sur les mélanges hydrocarbonés doivent etre respectées.
L'applicabilité de cette Norme européenne est décrite dans les normes produit sur les mélanges hydrocarbonés.
Bitumenske zmesi – Preskusne metode za vroče asfaltne zmesi – 26. del: Togost
General Information
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Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 12697-26:2005
01-januar-2005
%LWXPHQVNH]PHVL±3UHVNXVQHPHWRGH]DYURþHDVIDOWQH]PHVL±GHO 7RJRVW
Bituminous mixtures - Test methods for hot mix asphalt - Part 26: Stiffness
Asphalt - Prüfverfahren für Heißasphalt - Teil 26: Steifigkeit
Mélanges bitumineux - Méthodes d'essai pour mélange hydrocarboné a chaud - Partie
26: Module de rigidité
Ta slovenski standard je istoveten z: EN 12697-26:2004
ICS:
93.080.20 Materiali za gradnjo cest Road construction materials
SIST EN 12697-26:2005 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN 12697-26
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2004
ICS 93.080.20
English version
Bituminous mixtures - Test methods for hot mix asphalt - Part
26: Stiffness
Mélanges bitumineux - Méthodes d'essai pour mélange Asphalt - Prüfverfahren für Heißasphalt - Teil 26: Steifigkeit
hydrocarboné à chaud - Partie 26: Rigidité
This European Standard was approved by CEN on 1 April 2004.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2004 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12697-26:2004: E
worldwide for CEN national Members.
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EN 12697-26:2004 (E)
Contents
page
1 Scope .7
2 Normative references .7
3 Terms, definitions and symbols.7
3.1 Terms and definitions .7
3.2 Symbols .8
4 Principle.9
5 Sinusoidal loading.9
5.1 Test methods.9
5.1.1 General.9
5.1.2 Bending tests .10
5.1.3 lndirect tensile test .10
5.1.4 Direct uniaxial tests.10
5.2 Loading conditions.10
5.3 Load amplitudes .10
5.4 Loading frequencies.11
6 Controlled strain rate loading.11
6.1 Test method.11
6.2 Loading conditions.11
6.3 Strain amplitudes.11
6.3.1 Preliminary test.11
6.3.2 Strain amplitudes during the test.12
6.4 Test loading times .12
7 Temperatures .12
8 Expression of results .12
9 Test report .14
9.1 General.14
9.2 Information on specimen .15
9.3 Information on test method .15
9.4 Information on the test and results.15
9.5 Optional information .15
10 Precision.15
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 .18
A.4 Mode of operation.19
A.4.1 Stabilising the specimen.19
A.4.2 Procedure .19
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
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EN 12697-26:2004 (E)
B.3.1 Dimensions .23
B.3.2 Sample manufacture .23
B.4 Mode of operation .24
B.4.1 Stabilising the specimen .24
B.4.2 Procedure.24
Annex C (normative) Test applying Indirect tension to cylindrical specimens (IT-CY).26
C.1 Principle.26
C.2 Equipment .26
C.2.1 General devices .26
C.2.2 Test equipment .26
C.3 Specimen preparation.31
C.3.1 Preparation.31
C.3.2 Storage conditions.31
C.4 Mode of operation .32
C.4.1 Conditioning and test temperature.32
C.4.2 Mounting the specimen .32
C.4.3 Stiffness measurement.33
Annex D (normative) Direct tension-compression test on cylindrical specimens (DTC-CY) .35
D.1 Principle.35
D.2 Equipment .35
D.3 Specimen preparation.35
D.4 Mode of operation .37
D.4.1 Stabilising the specimen .37
D.4.2 Procedure.37
Annex E (normative) Test applying direct tension to cylindrical specimens (DT-CY) or to
prismatic specimens (DT-PR) .38
E.1 Principle.38
E.2 Equipment .38
E.3 Specimen preparation.38
E.3.1 Cylindrical specimen.38
E.3.2 Prismatic specimen.39
E.4 Mode of operation .39
E.4.1 Stabilisation of the specimen.39
E.4.2 Procedure.40
E.5 Derivation of the master-curve .41
E.5.1 Isotherms.41
E.5.2 Master curve at a fixed temperature.42
E.6 Determination of the stiffness modulus for the fixed loading time .44
3
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EN 12697-26:2004 (E)
Foreword
This document (EN 12697-26:2004) 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 January 2005, and conflicting national standards shall be withdrawn at
the latest by August 2005.
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
EN 12697-8, Bituminous mixtures — Test methods for hot mix asphalt — Part 8: Determination of void
characteristics of bituminous specimens
EN 12697-9, Bituminous mixtures — Test methods for hot mix asphalt — Part 9: Determination of the
reference density
EN 12697-10, Bituminous mixtures — Test methods for hot mix asphalt — Part 10: Compactibility
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 specimen
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
EN 12697-16, Bituminous mixtures — Test methods for hot mix asphalt — Part 16: Abrasion by studded tyres
4
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EN 12697-26:2004 (E)
EN 12697-17, Bituminous mixtures — Test methods for hot mix asphalt — Part 17: Particle loss of porous
asphalt specimen.
EN 12697-18, Bituminous mixtures — Test methods for hot mix asphalt — 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
Marshall specimens
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
EN 12697-24, Bituminous mixtures — Test methods for hot mix asphalt — Part 24: Resistance to fatigue
prEN 12697-25, Bituminous mixtures — Test methods for hot mix asphalt — Part 25: Cyclic compression test
EN 12697-26, Bituminous mixtures — Test methods for hot mix asphalt — 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 preparationby
impact compactor
EN 12697-31, Bituminous mixtures — Test methods for hot mix asphalt — Part 31: Specimen preparationby
gyratory compactor
EN 12697-32, Bituminous mixtures — Test methods for hot mix asphalt — Part 32: Laboratory compaction of
bituminous mixtures by a 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
prEN 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 pre-coated chippings for HRA
EN 12697-38, Bituminous mixtures — Test methods for hot mix asphalt — Part 38: Test equipment and
calibration
5
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EN 12697-26:2004 (E)
prEN 12697-39, Bituminous mixtures — Test methods for hot mix asphalt — Part 39: Binder content by
ignition
prEN 12697-40, Bituminous mixtures — Test methods for hot mix asphalt — Part 40: In-situ drainability
prEN 12697-41, Bituminous mixtures — Test methods for hot mix asphalt — Part 41: Resistance to de-icing
fluids
prEN 12697-42, Bituminous mixtures — Test methods for hot mix asphalt — Part 42: Amount of foreign
matters in reclaimed asphalt
prEN 12697-43, Bituminous mixtures — Test methods for hot mix asphalt — Part 43: Resistance to fuel
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland
and United Kingdom.
6
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EN 12697-26:2004 (E)
1 Scope
This document 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
shall be respected.
The applicability of this document is described in the product standards for bituminous mixtures.
2 Normative references
The following referenced documents are indispensable for the application 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.
EN 12697-6, Bituminous mixtures — Test methods for hot mix asphalt — Part 6: Determination of bulk density
of bituminous specimens
EN 12697-29, Bituminous mixtures — Test methods for hot mix asphalt — Part 29: Determination of the
dimensions of a bituminous specimen.
EN 12967-31, Bituminous mixtures — Test methods for hot mix asphalt — Part 31: Specimen preparation by
gyratory compactor.
EN 12967-33, Bituminous mixtures — Test methods for hot mix asphalt — 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
complex modulus
relationship between stress and strain for a linear visco-elastic material submitted to a sinusoidal load wave
σ × sin (ω × t) results in a strain ε × sin (ω × (t – Φ)) that has a phase
form at time, t, where applying a stress
angle, Φ, with respect to the stress
NOTE 1 The amplitude of strain and the phase angle are functions of the frequency, ω, and the test temperature, Θ.
NOTE 2 The stress strain ratio defines the complex modulus E* as:
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EN 12697-26:2004 (E)
E* = E* ×(cos (Φ) + i ×sin (Φ)) (1)
The complex modulus is characterised by a pair of two components. This pair can be expressed in two ways: the real
component E and the imaginary components E :
1 2
E = E* ×cos (Φ ) (2)
1
E = E* ×sin (Φ) (3)
2
the absolute value of the complex modulus |E*| and the phase angle, Φ:
2 2
E* = E + E (4)
1 2
E
2
Φ = arctan (5)
E
1
NOTE 3 This second characterisation 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 4 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 (Φ ≤ –20 °C). Then the complex modulus
reaches its highest possible value noted E .
∞
3.1.2
stiffness modulus
absolute value of the complex modulus |E*| or the value of the secant modulus
3.1.3
secant modulus
relationship between stress and strain at the loading time, t, for a material subjected to controlled strain rate
loading:
σ (t)
E(t) = (6)
ε (t)
with stress, σ(t), and strain, ε(t), at time t
NOTE 1 The strain law is:
n
ε (t) = α ×t (7)
i
where α and n are constants.
i
NOTE 2 Several successive tests may be carried out on the same specimen for different values α. For linear visco-
i
elastic materials, the secant modulus obtained for different values of α at the same temperature depends on the loading
i
time, t, only.
3.2 Symbols
For the purposes of thisdocument, the following symbols apply:
E* the complex modulus;
E the real component of the complex modulus;
1
8
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EN 12697-26:2004 (E)
E the imaginary component of the complex modulus;
2
E the highest possible value of the complex modulus;
∞
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);
k the load area factor;
l the length of the measurement area l , in millimetres (mm);
0 0
L the span length between outer supports in bending tests, in millimetres (mm);
t the loading time, in seconds (s);
S the stiffness modulus, in megapascals (MPa);
m
Θ the test temperature, in degrees celsius (°C);
z the displacement, in millimetres (mm);
ω the test frequency, in hertz (Hz);
Φ the phase angle, in degrees (°);
γ the form factor (a function of specimen size and form);
µ the mass factor (a function of the mass of the specimen and the mass of the movable parts that
influence the resultant force by their inertial effects);
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. The amplitudes of the stress and strain are measured, together with the phase difference between
stress and strain.
5 Sinusoidal loading
5.1 Test methods
5.1.1 General
The following test methods can be adopted by use of the relative form and mass factor (see clause 8). The
testing procedures that shall be followed are described in annex A, B, C, D and E. If other test procedures are
used to characterise stiffness properties of bituminous mixtures, the equivalence shall first by verified by
comparison with one of these procedures and a statement on that equivalence shall be attached to test
reports.
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EN 12697-26:2004 (E)
NOTE Inter-laboratory tests have shown that the following mentioned bending tests are in good agreement provided
that the equipment is carefully calibrated and that some basic guidelines are strictly followed.
5.1.2 Bending tests
The bending test options are:
2PB-TR: test applying two point bending to trapezoidal specimens, see annex A;
2PB-PR: test applying two point bending to prismatic specimens, see annex A;
3PB-PR: test applying three point bending to prismatic specimens, see annex B;
4PB-PR: test applying four point bending to prismatic specimens, see annex B.
5.1.3 lndirect tensile test
The indirect tensile test option is:
IT-CY: test applying indirect tension to cylindrical specimens, see annex C.
5.1.4 Direct uniaxial tests
The direct uniaxial test options are:
DTC-CY: test applying direct tension-compression to cylindrical specimens, see annex D;
DT-CY: test applying direct tension to cylindrical specimens, see annex E;
DT-PR: test applying direct tension to prismatic specimens, see annex E.
5.2 Loading conditions
The amplitude and the frequency of the loading signal shall be controlled by a feedback control, which may be
based either on the force or on the displacement.
NOTE The waveform should be harmonic. Any distortion is the sign of an abnormal set up or of a resonance
phenomenon that can disturb the measurement.
5.3 Load amplitudes
The amplitude of the load shall be such that no damage can be generated during the time needed to perform
the measurements.
NOTE 1 Experience with a number of test methods has shown that for most bituminous mixtures strains should be kept
–6
at a level lower than 50 microstrain (= 50 × 10 m/m) to prevent fatigue damage.
NOTE 2 It is known that, beyond certain levels of strain, non-linear behaviour (e.g. stress dependency) can be
displayed by the material. In such a case, the proportionality between stress and strain is no longer valid and the concept
of complex modulus defined above is no longer correct. This limit depends on the material but it also varies with
temperature for a given material.
NOTE 3 Special attention should be given in the highest range of temperature. Therefore, it is recommended to
perform linearity tests at the highest temperature to be undertaken within the testing programme. This test consists of
measuring the complex modulus at a fixed frequency for an increasing range of strains (or stresses) and to determine the
value of strain at which the modulus is no longer constant (starts to decrease).
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EN 12697-26:2004 (E)
NOTE 4 Attention should be paid to the danger of fatigue da
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