oSIST prEN 1097-2:2016

Tests for mechanical and physical properties of aggregates - Part 2: Methods for the determination of resistance to fragmentation

This European Standard describes the reference method, the Los Angeles test, used for type testing and in case of dispute (and an alternative method, the impact test) for determining the resistance to fragmentation of coarse aggregates (main text) and aggregates for railway ballast (Annex A). For other purposes, in particular factory production control, other methods may be used provided that an appropriate working relationship with the reference method has been established.
This European Standard applies to natural, manufactured or recycled aggregates used in building and civil engineering.
Annex A describes a method for the determination of resistance to fragmentation of aggregates for railway ballast.
Annex B gives alternative narrow range classifications for the Los Angeles test and the impact test.
Annex C contains construction, operation and safety requirements for the impact tester.
Annex D describes a method for checking of the impact tester.
Annex E gives precision data.
Annex F contains a worked example of calculation of impact value SZ.
Annex G gives an alternative narrow range classification for the Los Angeles test of 16/32 mm recycled aggregates.
Annex H proposes additional sieves for the evaluation of the Los Angeles test for railway ballast.
Annex A is normative and Annexes B to H are informative.

Prüfverfahren für mechanische und physikalische Eigenschaften von Gesteinskörnungen - Teil 2: Verfahren zur Bestimmung des Widerstandes gegen Zertrümmerung

Diese Europäische Norm beschreibt das Referenzverfahren, Los-Angeles-Prüfverfahren, das für die Erstprüfung und in Streitfällen zur Bestimmung des Widerstandes gegen Zertrümmerung von groben Gesteinskörnungen (Haupttext) und Gesteinskörnungen für Gleisschotter (Anhang A) verwendet wird (sowie den Schlagversuch als alternatives Verfahren). Für andere Zwecke, speziell im Rahmen der werkseigenen Produktionskontrolle, dürfen andere Verfahren angewendet werden, sofern ein ausreichender Zusammenhang zum Referenzverfahren nachgewiesen wurde.
Diese Europäische Norm wird angewendet für natürliche, industriell hergestellte oder rezyklierte Gesteinskörnungen, die im Bauwesen eingesetzt werden.
Anhang A beschreibt ein Verfahren zur Bestimmung des Widerstandes gegen Zertrümmerung von Gesteinskörnungen für Gleisschotter.
Anhang B beschreibt alternative, enge Kornklassen für das Los-Angeles-Prüfverfahren und den Schlagversuch.
Anhang C umfasst Aufbau, Betrieb und Sicherheitsanforderungen für das Schlagprüfgerät.
Anhang D beschreibt ein Verfahren zur Prüfung des Schlagprüfgeräts.
Anhang E enthält Daten zur Präzision.
Anhang F enthält ein bearbeitetes Beispiel zur Berechnung des Schlagzertrümmerungswertes SZ.
Anhang G beschreibt eine alternative, enge Kornklasse für das Los-Angeles-Prüfverfahren von rezyklierten Gesteinskörnungen der Kornklasse 16/32 mm.
Anhang H beschreibt zusätzliche Siebe zur Bewertung des Los-Angeles-Prüfverfahrens für Gleisschotter.
Anhang A ist normativ während Anhänge B bis H informativer Natur sind.

Essais pour déterminer les caractéristiques mécaniques et physiques de granulats - Partie 2 : Méthodes pour la détermination de la résistance à la fragmentation

Preskusi mehanskih in fizikalnih lastnosti agregatov - 2. del: Metode določevanja odpornosti proti drobljenju

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Sep-2016
• ICS: 91.100.15 - Mineral materials and products
• Technical Committee: AGR - Aggregates
• Current Stage: 98 - Abandoned project (Adopted Project)
• Start Date: 13-Jul-2018
• Due Date: 18-Jul-2018
• Completion Date: 13-Jul-2018
• Ref Project: prEN 1097-2 - Tests for mechanical and physical properties of aggregates - Part 2: Methods for the determination of resistance to fragmentation

Relations

• Revised: SIST EN 1097-2:2010 - Tests for mechanical and physical properties of aggregates - Part 2: Methods for the determination of resistance to fragmentation
• Effective Date: 01-Sep-2016
• Revised: SIST EN 1097-2:2010 - Tests for mechanical and physical properties of aggregates - Part 2: Methods for the determination of resistance to fragmentation
• Effective Date: 18-Jan-2023
• Revised: SIST EN 1097-2:2010 - Tests for mechanical and physical properties of aggregates - Part 2: Methods for the determination of resistance to fragmentation
• Effective Date: 19-Jan-2023
• Revised: SIST EN 1097-2:2010 - Tests for mechanical and physical properties of aggregates - Part 2: Methods for the determination of resistance to fragmentation
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 1097-2:2016
01-september-2016
3UHVNXVLPHKDQVNLKLQIL]LNDOQLKODVWQRVWLDJUHJDWRYGHO0HWRGHGRORþHYDQMD
RGSRUQRVWLSURWLGUREOMHQMX
Tests for mechanical and physical properties of aggregates - Part 2: Methods for the
determination of resistance to fragmentation
Prüfverfahren für mechanische und physikalische Eigenschaften von Gesteinskörnungen
- Teil 2: Verfahren zur Bestimmung des Widerstandes gegen Zertrümmerung
Essais pour déterminer les caractéristiques mécaniques et physiques de granulats -
Partie 2 : Méthodes pour la détermination de la résistance à la fragmentation
Ta slovenski standard je istoveten z: prEN 1097-2
ICS:
91.100.15 Mineralni materiali in izdelki Mineral materials and
products
oSIST prEN 1097-2:2016 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 1097-2:2016


DRAFT
EUROPEAN STANDARD
prEN 1097-2
NORME EUROPÉENNE

EUROPÄISCHE NORM

June 2016
ICS 91.100.15 Will supersede EN 1097-2:2010
English Version

Tests for mechanical and physical properties of aggregates
- Part 2: Methods for the determination of resistance to
fragmentation
Essais pour déterminer les caractéristiques Prüfverfahren für mechanische und physikalische
mécaniques et physiques de granulats - Partie 2 : Eigenschaften von Gesteinskörnungen - Teil 2:
Méthodes pour la détermination de la résistance à la Verfahren zur Bestimmung des Widerstandes gegen
fragmentation Zertrümmerung
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 154.

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
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1097-2:2016 E
worldwide for CEN national Members.

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Contents Page
European foreword . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Apparatus . 7
4.1 General apparatus . 7
4.2 Additional apparatus required for the determination of resistance to
fragmentation by the Los Angeles test method . 8
4.3 Additional apparatus required for the determination of resistance to
fragmentation by the impact test method . 9
5 Determination of resistance to fragmentation by the Los Angeles test method . 9
5.1 Principle . 9
5.2 Preparation of test portion . 9
5.3 Test procedure . 10
5.4 Calculation and expression of results . 10
5.5 Test report . 11
6 Determination of resistance to fragmentation by the impact test method . 11
6.1 Principle . 11
6.2 Preparation of test specimens . 12
6.3 Test procedure . 12
6.4 Calculation and expression of results . 13
6.5 Test report . 13
Annex A (normative) Determination of the resistance to fragmentation of aggregates
for railway ballast . 15
A.1 Apparatus . 15
A.2 Determination of the resistance to fragmentation by the Los Angeles test
method . 17
A.3 Determination of the resistance to fragmentation by the impact test method . 19
Annex B (informative) Alternative narrow range classifications for the Los Angeles
test and for the impact test . 21
B.1 Los Angeles test . 21
B.2 Impact test . 21
Annex C (informative) The impact tester: Construction, operation and safety
requirements . 22
C.1 General . 22
C.2 Construction . 22
C.3 Lifting device . 23
C.4 Sample holder . 23
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C.5 Anvil . 24
C.6 Base plate and dampers . 25
C.7 Safety requirements and testing . 25
C.8 Checking of impact tester . 25
Annex D (informative) Checking of the impact tester . 34
D.1 Scope and field of application . 34
D.2 Checklist . 34
D.3 Apparatus and test agents . 34
D.4 Procedure . 36
Annex E (informative) Precision . 38
E.1 General . 38
E.2 Los Angeles test . 38
E.3 Impact test . 38
Annex F (informative) Worked example of calculation of impact value SZ . 39
Annex G (informative) Alternative narrow range classification for the Los Angeles
test of 16/32 mm recycled aggregates . 40
Annex H (informative) Additional sieve for evaluation of the Los Angeles test for
railway ballast . 41
Bibliography . 42

3

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European foreword
This document (prEN 1097-2:2016) has been prepared by Technical Committee CEN/TC 154
“Aggregates”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 1097-2:2010.
The main technical changes compared to EN 1097-2:2010 are the following:
— All annexes are presented in the Scope.
— Guard sieves are introduced in Table 1.
— Notes with normative text are transformed into main text or deleted.
— Subclauses 5.5, 6.5, A.2.5 and A.3.5 Test report are revised.
— Annex A is completed to contain full text, not only the parts that are different from the main
text.
— Formula A.1 is revised.
— Annex B is completed with alternative narrow range classifications for the impact test.
— A new Annex H with additional sieves for evaluation of the Los Angeles test for railway
ballast is added.
— All references (except for the normative) are dated.
— The Bibliography is checked.
This European Standard forms part of a series of tests for mechanical and physical properties of
aggregates. Test methods for other properties of aggregates are covered by the following
European Standards:
— EN 932, Tests for general properties of aggregates
— EN 933, Tests for geometrical properties of aggregates
— EN 1367, Tests for thermal and weathering properties of aggregates
— EN 1744, Tests for chemical properties of aggregates
— EN 13179, Tests for filler aggregate used in bituminous mixtures
EN 1097 consists of the following parts, under the general title Tests for mechanical and physical
properties of aggregates:
— Part 1: Determination of the resistance to wear (micro-Deval)
— Part 3: Determination of loose bulk density and voids
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— Part 4: Determination of the voids of dry compacted filler
— Part 5: Determination of the water content by drying in a ventilated oven
— Part 6: Determination of particle density and water absorption
— Part 7: Determination of the particle density of filler – Pyknometer method
— Part 8: Determination of the polished stone value
— Part 9: Method for the determination of the resistance to wear by abrasion from studded
tyres — Nordic test
— Part 10: Water suction height
— Part 11: Determination of compressibility and confined compressive strength of lightweight
aggregates
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1 Scope
This European Standard describes the reference method, the Los Angeles test, used for type
testing and in case of dispute (and an alternative method, the impact test) for determining the
resistance to fragmentation of coarse aggregates (main text) and aggregates for railway ballast
(Annex A). For other purposes, in particular factory production control, other methods may be
used provided that an appropriate working relationship with the reference method has been
established.
This European Standard applies to natural, manufactured or recycled aggregates used in
building and civil engineering.
Annex A describes a method for the determination of resistance to fragmentation of aggregates
for railway ballast.
Annex B gives alternative narrow range classifications for the Los Angeles test and the impact
test.
Annex C contains construction, operation and safety requirements for the impact tester.
Annex D describes a method for checking of the impact tester.
Annex E gives precision data.
Annex F contains a worked example of calculation of impact value SZ.
Annex G gives an alternative narrow range classification for the Los Angeles test of 16/32 mm
recycled aggregates.
Annex H proposes additional sieves for the evaluation of the Los Angeles test for railway ballast.
Annex A is normative and Annexes B to H are informative.
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 932-1, Tests for general properties of aggregates - Part 1: Methods for sampling.
EN 932-2, Tests for general properties of aggregates - Part 2: Methods for reducing laboratory
samples.
EN 932-5, Tests for general properties of aggregates - Part 5: Common equipment and calibration.
EN 933-1, Tests for geometrical properties of aggregates - Part 1: Determination of particle size
distribution - Sieving method.
EN 933-2, Tests for geometrical properties of aggregates - Part 2: Determination of particle size
distribution - Test sieves, nominal size of apertures
EN 1097-6, Tests for mechanical and physical properties of aggregates - Part 6: Determination of
particle density and water absorption.
EN 10025-2, Hot rolled products of structural steels - Part 2: Technical delivery conditions for non-
alloy structural steels.
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3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
constant mass
mass determined after successive weighings at least 1 h apart not differing by more than 0,1 %
Note 1 to entry: In many cases constant mass can be achieved after a test portion has been dried for a
pre-determined period in a specified oven (see 4.1.3) at (110 ± 5) °C. Test laboratories may determine the
time required to achieve constant mass for specific types and sizes of sample dependent upon the drying
capacity of the oven used.
3.2
impact value, SZ
value SZ which gives a measure of the resistance of aggregates to dynamic crushing; it is equal
to one fifth of the sum of the mass percentages of the tested sample passing through five
specified test sieves when tested in accordance with Clause 6
3.3
laboratory sample
sample intended for laboratory testing
3.4
Los Angeles coefficient, LA
percentage of the test portion passing a pre-determined sieve after completion of the test
3.5
test portion
sample used as a whole in a single test
3.6
test specimen
sample used in a single determination when a test method requires more than one
determination of a property
4 Apparatus
Unless otherwise stated, all apparatus shall conform to the general requirements of EN 932-5.
4.1 General apparatus
4.1.1 Test sieves, conforming to EN 933-2 with aperture sizes as specified in Table 1.
Table 1 — Test sieves
Test Aperture size
 mm
Los Angeles 1,6; 10; 11,2 (or 12,5); 14
a
Impact test 0,2; 0,63; 2; 5; 8; 10; 11,2; 12,5
a
For the impact test, because of the tolerances in the sieve openings, the same 8 mm test sieve used for the

preparation of the test portion should again be used for the evaluation of the test.
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4.1.2 Guard sieve, e.g. 2 mm, 4 mm or 8 mm.
4.1.3 Balance, capable of weighing the test portion to an accuracy of 0,1 % of the mass of the
test portion.
4.1.4 Ventilated oven, controlled to maintain a temperature of (110 ± 5) °C.
4.2 Additional apparatus required for the determination of resistance to
fragmentation by the Los Angeles test method
4.2.1 Equipment, for reducing the laboratory sample to a test portion, as described in
EN 932-2.
4.2.2 Los Angeles test machine, comprising the following essential parts.
NOTE An example of a machine that has been found to be satisfactory is shown in Figure 1.
Dimensions in millimetres

Key
1 internal length (508 ± 5)
2 internal diameter (711 ± 5)
3 shelf
4 cover and opening
5 rotation
Figure 1 — Typical Los Angeles testing machine
+1,0
12
−0,5
4.2.2.1 Hollow drum, made of structural steel plate ( ) mm thick conforming to grade
S275 of EN 10025-2 which has been selected to be formed without undue stress, and can be
welded without significant distortion. The drum shall be closed at both ends. It shall have an
internal diameter of (711 ± 5) mm and an internal length of (508 ± 5) mm. The drum shall be
supported on two horizontal stub axles fixed to its two end walls but not penetrating inside the
drum; the drum shall be mounted so that it rotates about a horizontal axis.
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An opening (150 ± 3) mm wide shall be provided, preferably over the whole length of the drum,
to facilitate insertion and removal of the sample after the test. During the test, the opening shall
be sealed so that it is dustproof, by using a removable cover which enables the inside surface to
remain cylindrical.
The cylindrical inner surface shall be interrupted by a projecting shelf, placed between 380 mm
and 820 mm from the nearest edge of the opening. The distance shall be measured along the
inside of the drum in the direction of rotation. The shelf shall have a rectangular cross section
(length equal to that of the drum, width (90 ± 2) mm, thickness (25 ± 1) mm) and it shall be
placed in a diametrical plane, along a generating line, and shall be rigidly fixed in place.
The shelf shall be replaced when its width at any point wears to less than 86 mm and its
thickness at any point along the front edge wears to less than 23 mm.
The base of the machine shall be supported directly on a level concrete or stone block floor.
The removable cover should be made of the same steel as the drum. The projecting shelf should
be made of the same steel or a harder grade.
4.2.2.2 Ball load, consisting of 11 spherical steel balls, each with a diameter of between
45 mm and 49 mm (see Annex B). Each ball shall weigh between 400 g and 445 g, and the total
load shall weigh between 4 690 g and 4 860 g.
NOTE 1 The lower limit deviation of the ball mass is a working tolerance limit.
NOTE 2 A hardness of the steel balls between HRC 60 and HRC 66 is suitable.
4.2.2.3 Motor, imparting a rotational speed to the drum of between 31 r/min and 33 r/min.
4.2.2.4 Tray, for recovering the material and the ball load after testing.
4.2.2.5 Revolution counter, which will automatically stop the motor after the required
number of revolutions.
4.3 Additional apparatus required for the determination of resistance to
fragmentation by the impact test method
4.3.1 Impact tester, see Annex C.
4.3.2 Equipment for testing the accuracy of the impact tester, see Annex D.
4.3.3 Brush and bowls.
5 Determination of resistance to fragmentation by the Los Angeles test
method
5.1 Principle
A sample of aggregate is rolled with steel balls in a rotating drum. After rolling is complete, the
quantity of material retained on a 1,6 mm sieve is determined.
5.2 Preparation of test portion
The mass of the laboratory sample shall have at least 15 kg of particles in the 10 mm to 14 mm
size range.
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The test shall be carried out on aggregate passing the 14 mm test sieve and retained on the
10 mm test sieve. In addition, the grading of the test portion shall comply with at least one of the
following requirements:
a) between 60 % and 70 % passing a 12,5 mm test sieve;
b) between 30 % and 40 % passing a 11,2 mm test sieve.
NOTE 1 The additional grading requirements allow the test portion to be created from product sizes
other than 10/14 (see Annex B).
NOTE 2 For recycled aggregates, a test procedure for the 16/32 mm size fraction is described in
Annex G.
Sieve the laboratory sample using the 10 mm, 11,2 mm (or 12,5 mm) and 14 mm test sieves to
give separate fractions in the ranges 10 mm to 11,2 mm (or 12,5 mm) and 11,2 mm (or
12,5 mm) to 14 mm.
Wash each fraction on the sieve defining the lower limit of the size fraction. Dry the fractions to
constant mass at (110 ± 5) °C.
For temperature-sensitive recycled aggregates, a drying temperature of (40 ± 5) °C should be
used.
Allow the fractions to cool to ambient temperature. Mix the two fractions to provide a modified
10 mm to 14 mm laboratory sample which complies with the appropriate additional grading
requirement given above.
Reduce the modified laboratory sample prepared from the mixed fractions to test portion size in
accordance with EN 932-2. The test portion shall have a mass of (5 000 ± 5) g.
It is also acceptable to directly reduce the mass of each individual size fraction to its required
mass in the test portion.
5.3 Test procedure
Check that the drum is clean before loading the sample. Carefully place the balls in the machine,
then the test portion. Replace the cover and rotate the machine for 500 revolutions at a constant
speed between 31 r/min and 33 r/min.
Pour the aggregate into a tray placed under the apparatus, taking care that the opening is just
above the tray in order to avoid losing any material. Clean out the drum, removing all fines,
paying particular attention around the projecting shelf. Carefully remove the ball load from the
tray, taking care not to lose any aggregate particles.
Transfer the material on the tray to the 1,6 mm sieve, protected by a guard sieve if appropriate,
and wash the material in a stream of clean water until the water beneath the sieve runs clear.
Place the aggregate particles retained on the guard sieve and the 1,6 mm test sieve onto a tray.
Dry the portion retained on the 1,6 mm sieve at a temperature of (110 ± 5) °C (or lower, see
subclause 5.2) until a constant mass is achieved. Record the mass, m, to the nearest gram.
5.4 Calculation and expression of results
Calculate the Los Angeles coefficient LA from the following formula:
LA 5000−m
(1)
50
10
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where
m is the mass retained on the 1,6 mm sieve, in grams.
Report the result to the nearest whole number.
NOTE A statement on the precision of the Los Angeles test is given in Annex E.
5.5 Test report
5.5.1 Required data
The test report shall include the following information:
a) reference to this European Standard;
b) identification of the test sample, including identification of the source;
c) identification of the laboratory;
d) date of test;
e) Los Angeles coefficient, LA, to the nearest whole number;
f) deviations from the reference method – if any.
5.5.2 Optional data
The test report may include the following information:
a) reference to the chosen sampling procedure;
b) reference to the chosen sample reduction procedure;
c) mass of the test portion;
d) used size fractions to form the test portion 10/14 mm;
e) sampling report, if available;
f) sample reception date if different from sampling date;
g) other influencing parameters (e.g. weather conditions, …).
6 Determination of resistance to fragmentation by the impact test method
6.1 Principle
A test specimen is placed in a steel cylinder and subjected to ten impacts from a hammer of
mass 50 kg, falling from a specified height. The amount of fragmentation caused by the ten
impacts is measured by sieving the test specimen using five specified test sieves.
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6.2 Preparation of test specimens
6.2.1 A laboratory sample shall be obtained in accordance with EN 932-1. The sample shall
contain at least 5 kg of the size fraction 8 mm to 10 mm and 2,5 kg of each of the size fractions
10 mm to 11,2 mm and 11,2 mm to 12,5 mm.
6.2.2 A quantity of the size fractions 8 mm to 10 mm, 10 mm to 11,2 mm and 11,2 mm to
12,5 mm sufficient for at least three test specimens (see 6.2.3 and 6.2.4) shall be prepared from
the laboratory sample using the sieves 8 mm, 10 mm, 11,2 mm and 12,5 mm specified in 4.1.1.
Wash each fraction on the sieve defining the lower limit of the size fraction. Dry the fractions to
constant mass at (110 ± 5) °C. Allow the fractions to cool to ambient temperature.
For temperature-sensitive recycled aggregates, a drying temperature of (40 ± 5) °C should be
used.
6.2.3 Material for at least three test specimens shall be recombined as follows and three test
specimens shall be tested (see 6.2.4). The test specimens shall be composed of 50 % of the size
fraction 8 mm to 10 mm, 25 % of the size fraction 10 mm to 11,2 mm and 25 % of the size
fraction 11,2 mm to 12,5 mm and be weighed to the nearest 0,5 g. The three fractions shall be
mixed thoroughly prior to weighing of the test specimen as described in 6.2.4.
6.2.4 The mass of the test specimen in kilograms shall be 0,5 times the value of the particle
density in megagrams per cubic metre as determined in accordance with EN 1097-6 on a
sample composed as specified in 6.2.3.
If this particle density is known from previous tests, that result can be used.
For each test specimen the quantities, in kilograms, are:
a) size fraction 8 mm to 10 mm: 0,25 times the particle density;
b) size fraction 10 mm to 11,2 mm: 0,125 times the particle density;
c) size fraction 11,2 mm to 12,5 mm: 0,125 times the particle density.
The mass of a test specimen, referred to as M, prior to the testing shall not differ by more than
1 % from the nominal mass.
6.3 Test procedure
6.3.1 The test specimen shall be poured into the mortar of the impact test machine and its
surface roughly evened by hand without jigging. The pestle shall be pressed by the
corresponding device onto the test specimen and the hammer lifted up to a height of 370 mm.
The test specimen shall then be subjected to ten blows by the hammer.
6.3.2 Afte
...