9 4.2 Reagents for determination of water-soluble chloride salts using the Volhard method Clause 7 .... 15 5.3 Additional apparatus required for determination of water-soluble chloride s
Trang 2National foreword
This British Standard is the UK implementation of
EN 1744-1:2009+A1:2012 It supersedes BS EN 1744-1:2009, which is withdrawn
The start and finish of text introduced or altered by amendment is indicated in the text by tags Tags indicating changes to CEN text carry the number of the CEN amendment For example, text altered
by CEN amendment A1 is indicated by !".The UK participation in its preparation was entrusted by Technical Committee B/502, Aggregates to Subcommittee B/502/6, Test methods
A list of organizations represented on this subcommittee can be obtained on request to its secretary
This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application
Compliance with a British Standard cannot confer immunity from legal obligations.
This British Standard
was published under the
authority of the Standards
Policy and Strategy
Committee on 31 May 2010.
© The British Standards
Institution 2013 Published by
BSI Standards Limited 2013
Amendments/corrigenda issued since publication
31 January 2013 Implementation of CEN amendment A1:2012
Trang 3NORME EUROPÉENNE
English Version Tests for chemical properties of aggregates - Part 1: Chemical
analysis
Essais visant à déterminer les propriétés chimiques des
granulats - Partie 1: Analyse chimique
Prüfverfahren für chemische Eigenschaften von Gesteinskörnungen - Teil 1: Chemische Analyse
This European Standard was approved by CEN on 17 October 2009 and includes Amendment 1 approved by CEN on 15 October 2012 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom
EUROPEAN COMMITTEE FOR STANDARDIZATION
C O M I T É E U R O P É E N D E N O R M A L I S A T I O N
E U R O P Ä I S C H E S K O M I T E E FÜ R N O R M U N G
Management Centre: Avenue Marnix 17, B-1000 Brussels
Trang 4Contents Page
Foreword 7
1 Scope 8
2 Normative references 8
3 Terms and definitions 9
4 Reagents 9
4.1 General 9
4.2 Reagents for determination of water-soluble chloride salts using the Volhard method (Clause 7) 10
4.3 Reagents for determination of water-soluble chloride salts by potentiometry (Clause 8) 11
4.4 Reagent for factory production control determination of water-soluble chloride salts using the Mohr method (Clause 9) 11
4.5 Reagents for determination of water-soluble sulfates (Clause 10) 11
4.6 Reagents for determination of total sulfur content (Clause 11) 11
4.7 Reagents for determination of acid soluble sulfide content (Clause 13) 11
4.8 Reagents for determination of lightweight contaminators (see 14.2) 13
4.9 Reagents for determination of potential presence of humus (see 15.1) 13
4.10 Reagents for determination of fulvo acid content (see 15.2) 13
4.11 Reagents for determination of free lime by complexometry (see 18.2) 14
4.12 Reagent for determination of free lime by conductometry (see 18.3) 14
4.13 Reagents for determination of free lime by acidimetry (see 18.4) 14
4.14 Reagent for the determination of the expansion of steel slag (see 19.3) 15
4.14.1 Silicone oil 15
4.14.2 Hydrochloric acid diluted (1 + 5) 15
5 Apparatus 15
5.1 General requirements 15
5.2 Apparatus for general purposes 15
5.3 Additional apparatus required for determination of water-soluble chloride salts following Volhard (see Clause 7) 16
5.4 Additional apparatus required for potentiometric determination of water-soluble chloride salts (see Clause 8) 16
5.5 Additional apparatus required for factory production control determination of water soluble chloride salts following Mohr (see Clause 9) 17
5.6 Additional apparatus required for determination of water-soluble sulfates (see Clause 10) 17
5.7 Additional apparatus required for the determination of total sulfur content (see Clause 11) 17
5.8 Additional apparatus required for determination of sulfide content (see Clause 13) 17
5.9 Additional apparatus required for determination of lightweight contaminators (see 14.2) 18
5.10 Additional apparatus required for determination of the potential presence of humus (see 15.1) 18
5.11 Additional apparatus required for determination of fulvo acid content (see 15.2) 19
5.12 Additional apparatus required for determination of organic contaminators by mortar method (see 15.3) 19
5.13 Additional apparatus required for determination of free lime by complexometry (see 18.2) 19
5.14 Additional apparatus required for determination of free lime by conductometry (see 18.3) 19
Trang 55.15 Additional apparatus required for acidimetric determination of free lime (see 18.4) 22
5.16 Additional apparatus required for the determination of CaO in steel slag by X-ray diffraction (see 18.5) 22
5.17 Additional apparatus required for the determination of dicalcium silicate disintegration of air-cooled blast-furnace slag (see 19.1) 23
5.18 Additional apparatus required for determination of the volume expansion of steel slag (see 19.3) 23
6 General requirements for testing 26
6.1 Number of tests 26
6.2 Repeatability and reproducibility 26
6.3 Expression of mass, volume, factors and results 26
6.4 Drying of materials 26
6.5 Ignitions of precipitates 27
6.6 Check for the absence of chloride ions (silver nitrate test) 27
7 Determination of water-soluble chloride salts using the Volhard method (Reference method) 27
7.1 Principle 27
7.2 Sampling 27
7.3 Preparation of test specimens 27
7.4 Preparation of extracts 28
7.5 Procedure for the determination of the chloride content of the extracts 28
7.6 Calculation and expression of results 29
8 Determination of water-soluble chloride salts by potentiometry (Alternative method) 29
8.1 Principle 29
8.2 Sampling, preparation of test specimens and extracts 29
8.3 Procedure for the determination of the chloride content of the extracts 29
8.4 Calculation and expression of results 30
9 Determination of water-soluble chloride salts using the Mohr method (Alternative method) 30
9.1 General 30
9.2 Principle 30
9.3 Sampling 30
9.4 Preparation of test portion 31
9.5 Preparation of extracts 31
9.6 Procedure for the determination of the chloride content of the extracts 31
9.7 Calculation and expression of results 31
10 Determination of water-soluble sulfates 31
10.1 Determination of water soluble sulfates in natural and manufactured aggregates 31
10.1.1 Principle 31
10.1.2 Sampling 32
10.1.3 Preparation of test portion 32
10.1.4 Preparation of extracts 32
10.1.5 Procedure for the determination of the sulfate content of the extracts 32
10.1.6 Calculation and expression of results 33
10.2 Determination of water soluble sulfates in recycled aggregates 33
10.2.1 Principle 33
10.2.2 Sampling 33
10.2.3 Preparation of test specimen 34
10.2.4 Preparation of extracts 34
10.2.5 Procedure for the determination of the sulfate content of the extracts, using a spectrophotometer 34
11 Determination of total sulfur content 35
11.1 Determination of total sulfur content by acid digestion (Reference method) 35
11.2 Determination of total sulfur content by high temperature combustion (Alternative method) 37
Trang 611.2.1 Principle 37
11.2.2 Sampling 37
11.2.3 Preparation of test portion 37
11.2.4 Procedure 37
11.2.5 Calculation and expression of results 37
12 Determination of acid soluble sulfates 37
12.1 Principle 37
12.2 Sampling 38
12.3 Preparation of test portion 38
12.4 Procedure 38
12.5 Calculation and expression of results 38
13 Determination of acid soluble sulfides 39
13.1 Principle 39
13.2 Sampling 39
13.3 Preparation of test portion 39
13.4 Procedure 39
13.5 Calculation and expression of results 40
14 Determination of components affecting the surface finish of concrete 40
14.1 Examination for the presence of reactive iron sulfide particles 40
14.1.1 General 40
14.1.2 Sampling 40
14.1.3 Procedure 41
14.2 Determination of lightweight contaminators 41
14.2.1 General 41
14.2.2 Principle 41
14.2.3 Procedure 41
14.2.4 Calculation and expression of results 42
15 Determination of organic components affecting the setting and the hardening of cement 42
15.1 Determination of potential presence of humus 42
15.1.1 Principle 42
15.1.2 Sampling 42
15.1.3 Preparation of test portion 42
15.1.4 Procedure 43
15.1.5 Expression of results 43
15.2 Determination of fulvo acid content 43
15.2.1 Principle 43
15.2.2 Sampling 43
15.2.3 Preparation of test portion 43
15.2.4 Procedure 43
15.2.5 Expression of results 44
15.3 Determination of organic contaminators by mortar method 44
15.3.1 Principle 44
15.3.2 Sampling 44
15.3.3 Preparation of test portions 44
15.3.4 Preliminary treatment of test portions 44
15.3.5 Constituents 45
15.3.6 Mix quantities 45
15.3.7 Mixing procedure 45
15.3.8 Measurement of stiffening time 46
15.3.9 Compressive strength of hardened mortar 46
15.3.10 Calculation and expression of results 46
16 Determination of water solubility 47
16.1 Determination of water solubility of aggregate, excluding filler 47
16.1.1 Principle 47
16.1.2 Sampling 47
16.1.3 Preparation of test portion 47
Trang 716.1.4 Extraction of soluble components 47
16.1.5 Calculation and expression of results 47
16.2 Determination of water solubility of filler 48
16.2.1 Principle 48
16.2.2 Sampling 48
16.2.3 Preparation of test portion 48
16.2.4 Extraction of soluble component 48
16.2.5 Calculation and expression of results 48
17 Determination of loss on ignition 49
17.1 Principle 49
17.2 Sampling and preparation of test portion 49
17.3 Procedure for the determination of loss on ignition 49
17.4 Calculation and expression of results 49
18 Determination of free lime in steel slag 50
18.1 General 50
18.2 Determination of free lime by complexometry (Reference method) 50
18.2.1 Principle 50
18.2.2 Sampling and preparation of test portion 50
18.2.3 Procedure 50
18.2.4 Calculation and expression of results 51
18.3 Determination of free lime by conductometry (Alternative method) 51
18.3.1 Principle 51
18.3.2 Sampling and preparation of test portion 51
18.3.3 Procedure 51
18.3.4 Evaluation and expression of results 51
18.4 Determination of free lime by acidimetry (Alternative method) 51
18.4.1 Principle 51
18.4.2 Sampling and preparation of test portion 52
18.4.3 Procedure 52
18.4.4 Calculation and expression of results 52
18.5 Determination of CaO in steel slag by X-ray diffraction 52
18.5.1 Principle 52
18.5.2 Procedure of analysis 53
18.5.3 Calibration procedure 54
18.5.4 Analytical results 55
19 Determination of unsoundness of blast-furnace and steel slags 55
19.1 Determination of dicalcium silicate disintegration of air-cooled blast-furnace slag 55
19.1.1 General 55
19.1.2 Principle 55
19.1.3 Sampling 55
19.1.4 Preparation of test portion 55
19.1.5 Procedure 55
19.1.6 Expression of results 55
19.2 Determination of iron disintegration of air-cooled blast-furnace slag 56
19.2.1 General 56
19.2.2 Principle 56
19.2.3 Sampling 56
19.2.4 Procedure 56
19.2.5 Expression of results 56
19.3 Determination of the expansion of steel slag 56
19.3.1 General 56
19.3.2 Principle 56
19.3.3 Sampling 56
19.3.4 Preparation and compaction of the specimens 56
19.3.5 Steam test procedure 58
19.3.6 Calculation and expression of results 58
Annex A (informative) Precision 60
Trang 8A.1 Symbols 60
A.2 Determination of water-soluble chloride salts using the Volhard method
(Reference method) (See Clause 7) 60
A.3 Determination of water-soluble chloride salts by potentiometry (Alternative
method) (See Clause 8) 60
A.4 Determination of water-soluble sulfates in recycled aggregate (See 10.2) 60
A.5 Determination of total sulfur content by acid digestion (Reference method) (See
11.1) 60
A.6 Determination of acid soluble sulfates (See Clause 12) 61
Bibliography 62
Trang 9Foreword
This document (EN 1744-1:2009+A1:2012) has been prepared by Technical Committee CEN/TC 154
“Aggregates”, the secretariat of which is held by BSI
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 May 2012, and conflicting national standards shall be withdrawn at the latest by May 2012
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights
This document supersedes !EN 1744-1:2009"
This document includes Amendment 1, approved by CEN on 2012-10-15
The start and finish of text introduced or altered by amendment is indicated in the text by tags ! " This standard forms part of a series of tests for chemical properties of aggregates Test methods for other properties of aggregates are covered by the following European Standards:
EN 932 (all parts), Tests for general properties of aggregates
EN 933 (all parts), Tests for geometrical properties of aggregates
EN 1097 (all parts), Tests for mechanical and physical properties of aggregates
EN 1367 (all parts), Tests for thermal and weathering properties of aggregates
The other parts of EN 1744, Tests for chemical properties of aggregates, are:
cement
According to the CEN/CENELEC Internal Regulations, the national standards organisations 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, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom
Trang 101 Scope
This European Standard specifies procedures for the chemical analysis of aggregates It specifies the reference procedures and, in certain cases, an alternative method which can be considered as giving equivalent results
Unless otherwise stated, the test methods specified in this standard may be used for factory production control, for audit tests or for type tests
This standard describes the reference methods used for type testing and in cases of dispute (and alternatives methods) for chemical analyses of aggregates For the purpose of type testing and in cases
of dispute only the reference method should be used 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
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 196-1, Methods of testing cement — Part 1: Determination of strength
EN 196-2:2005, Methods of testing cement — Part 2: Chemical analysis of cement
EN 459-2, Building lime — Part 2: Test methods
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 932-6, Tests for general properties of aggregates — Part 6: Definitions of repeatability and
reproducibility
EN 933-2, Tests for geometrical properties of aggregates — Part 2: Determination of particle size
distribution — Test sieves, nominal size of apertures
EN 1015-4, Methods of test for mortar for masonry — Part 4: Determination of consistence of fresh
mortar (by plunger penetration)
EN 1015-9, Methods of test for mortar for masonry — Part 9: Determination of workable life and
correction time of fresh mortar
EN 1015-11, Methods of test for mortar for masonry — Part 11: Determination of flexural and
compressive strength of hardened mortar
EN 1097-6, Tests for mechanical and physical properties of aggregates — Part 6: Determination of
particle density and water absorption
ISO 384:1978, Laboratory glassware — Principles of design and construction of volumetric glassware ISO 385, Laboratory glassware — Burettes
Trang 11ISO 648, Laboratory glassware — Single-volume pipettes
ISO 649-1, Laboratory glassware — Density hydrometers for general purposes — Part 1: Specification ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 4788, Laboratory glassware — Graduated measuring cylinders
DIN 12242-1:1980, Laboratory glassware; interchangeable conical ground joints, dimensions, tolerances
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply
successive weighings after drying at least 1 h apart not differing by more than 0,1 %
NOTE In many cases constant mass can be achieved after a test portion has been dried for a determined period in a specified oven at (110 ± 5) °C Test laboratories can determine the time required to achieve constant mass for specific types and sizes of sample dependent upon the drying capacity of the oven used
pre-4 Reagents
4.1 General
4.1.1 Unless otherwise stated, use only analytical grade reagents and demineralized water, or
water of equivalent purity
NOTE 1 Unless otherwise stated "%" means "% by mass"
NOTE 2 Where no tolerances are given for reagent volumes or masses, the values quoted are approximate
In such cases volumes delivered from measuring cylinders and indicated masses using the ordinary balances specified in 5.2.4 and 5.2.5 are considered sufficiently accurate for the purposes of this European Standard NOTE 3 Unless otherwise stated reagent solutions may be assumed to have long-term stability
NOTE 4 All chemicals should be treated as potential poisons with toxic properties and appropriate precautions taken before their use Always take time to assess possible hazards before starting any procedures and constant attention should be maintained
Trang 124.1.2 Concentrated liquid reagents shall have the following densities in g/cm³ at 20 °C:
The degree of dilution shall be indicated as a volumetric sum
NOTE 1 For example in 4.11.4, "hydrochloric acid (1+1)" means that 1 volume of concentrated hydrochloric acid is to be mixed with 1 volume of water
NOTE 2 Ready for use solutions may be used as an alternative
4.2 Reagents for determination of water-soluble chloride salts using the Volhard method (Clause 7)
4.2.1 Silver nitrate (AgNO3) solution, 0,100 mol/l, prepared by drying about 20 g of silver nitrate for
at least 1 h at a temperature of (110 ± 5) °C, left to cool in a desiccator and then weighing (16,987 ± 0,001) g of the dried silver nitrate, dissolving in water and diluting to 1 l in a volumetric flask (5.3.6) Store the solution in the amber-coloured glass reagent bottle (5.2.14) and protect from prolonged exposure to sunlight
4.2.2 Thiocyanate (KSCN or NH4SCN) solution, approximately 0,1 mol/l, prepared by dissolving 9,7 g of potassium thiocyanate or 7,6 g ammonium thiocyanate in water and diluting to 1 l in a volumetric flask
Pipette 25 ml of silver nitrate solution (4.2.1) into a conical flask (5.3.5) and add 5 ml of nitric acid (4.2.3) and 1 ml of ammonium iron (III) sulfate indicator solution (4.2.5)
Add the thiocyanate solution from a burette (5.2.13) until the first permanent colour change occurs, that
is from white opalescence to pale brown Note the volume of thiocyanate solution added
Calculate the concentration of the thiocyanate solution c T, (in mol/l), from the following equation:
where
Standardize the solution at weekly intervals, or before use if the tests are less frequent
4.2.3 Nitric acid (HNO3), approximately 6 mol/l, prepared by adding 100 ml of nitric acid (4.1) to
150 ml water, boiling the diluted acid in a fume cupboard (5.2.17) until it is colourless and leave to cool to room temperature
4.2.4 Chloride free technical grade 3,5-trimethylhexan-1-ol
4.2.5 Ammonium iron (III) sulfate NH4Fe(SO4)2.12H2O indicator solution, prepared by adding 60 g
of water to 50 g ammonium iron (III) sulfate, warming to dissolve, and adding 10 ml nitric acid (4.2.3) Leave the solution to cool to room temperature and store in a glass bottle (5.2.15)
Trang 134.3 Reagents for determination of water-soluble chloride salts by
potentiometry (Clause 8)
4.3.1 Silver nitrate (AgNO3) solution, 0,01 mol/l, prepared using the same procedure as specified
in 4.2.1, but dissolving 1,699 g of dried silver nitrate in a 1 l volumetric flask (5.3.6)
4.3.2 Sodium chloride (NaCl) solution, 0,02 mol/l, prepared by drying about 2 g of sodium chloride
at a temperature of (110 ± 5) °C for 1 h to 2 h, leaving to cool and then weighing (1,169 ± 0,001) g of the dried sodium chloride, dissolving in water and diluting to 1 l in a volumetric flask (5.3.6)
4.4 Reagent for factory production control determination of water-soluble chloride salts using the Mohr method (Clause 9)
water
4.5 Reagents for determination of water-soluble sulfates (Clause 10)
4.5.1 Hydrochloric acid (HCl) solution, made by adding 200 ml concentrated hydrochloric acid (4.1)
to 800 ml water
4.5.2 Barium chloride (BaCl2) solution, made by dissolving 100 g of barium chloride (BaCl2.2H2O)
in 1 l of water, and filtered through a medium grade filter paper before use
4.6 Reagents for determination of total sulfur content (Clause 11)
4.6.1 Hydrogen peroxide (H2O2), 30 % concentration
4.6.2 Indicator methyl red (dissolve 20 mg methyl red powder in 50 ml of ethanol, then add 50 ml of
water)
4.7 Reagents for determination of acid soluble sulfide content (Clause 13)
4.7.1 Lead acetate solution, made by dissolving approximately 0,2 g of lead acetate
4.7.2 Ammoniacal zinc sulfate solution, made by dissolving 50 g of zinc sulfate (ZnSO4.7H2O) in
least 24 h and filter through a medium grade filter paper
4.7.3 Tin (II) chloride (SnCl2.2H2O)
4.7.4 Metallic chromium (Cr), in powder form
4.7.5 Standard potassium iodate solution containing 0,016 7 mol/l, made by dissolving successively
in freshly boiled and cooled water in a 1 l volumetric flask, (3,6 ± 0,1) g to the nearest 0,1 mg (6.3) of
and 25 g of potassium iodide (KI) Make up to the mark with freshly boiled and cooled water
NOTE 1 A trace of sodium hydroxide will help to stabilize this solution The solution should be discarded when
it becomes discoloured
The factor F of this solution is calculated from the following equation:
8 566
,
3
m
Trang 14where
NOTE 2 The value of factor F for the solution should be calculated using the mean value of three
determinations, expressed to three decimal places
NOTE 3 If the sulfide content is less than 0,1 % by mass, solutions ten times less concentrated should be
used They are prepared by pipetting 100 ml of the solutions (4.7.5 and 4.7.6) into 1 l volumetric flasks and
making up to the mark with water
4.7.6 Sodium thiosulfate solution approximately 0,1 mol/l, made by dissolving 24,82 g of sodium
thiosulfate (Na2S2O3.5H2O) in water and making up to 1 l
Before each test series, determine the factor f of this solution using one of the two methods that follow
a) Standardization (preferred method) in relation to the standard potassium iodate solution (4.7.5)
Pipette 20 ml of the standard potassium iodate solution into a 500 ml conical flask and dilute with
approximately 150 ml of water Acidify with 25 ml of hydrochloric acid (1 + 1) and titrate with the
approximately 0,1 mol/l sodium thiosulfate solution to a pale yellow colour
Then add 2 ml of the starch solution (4.7.7) and continue the titration until the colour changes from blue
to colourless
The factor f of this solution is calculated from the following equation:
2 2
20 8
566 , 3
01 , 214 67 016 , 0
20
V
F V
NOTE 1 3,566 8 g/l of potassium iodate corresponds to a solution with exactly 0,016 67 mol/l of potassium
iodate and 214,01 is the molecular mass of KIO3
b) Standardization in relation to a known quantity of potassium iodate
Place (70 ± 5) mg of potassium iodate in a 500 ml conical flask and dissolve in approximately 150 ml
of water
Add about 1 g of potassium iodide, acidify with 25 ml of hydrochloric acid (1 + 1) and titrate with the
approximately 0,1 mol/l sodium thiosulfate solution until a pale yellow colour is obtained Then add 2 ml
of the starch solution (4.7.7) and titrate until the colour changes from blue to colourless
The factor f of this solution is calculated from the following equation:
V
m V
m f
3
2 3
2 280 , 363 4 8
Trang 15V3 is the volume of the approximately 0,1 mol/l sodium thiosulfate solution used for the titration
NOTE 2 3,566 8 g/l of potassium iodate corresponds to a solution with exactly 0,016 67 mol/l of potassium iodate
NOTE 3 The value of factor f for the solution should be calculated using the mean value of three
determinations, expressed to three decimal places
4.7.7 Starch solution, made taking 1 g of starch (water soluble), adding 1 g of potassium iodide KI,
dissolving in water and making up to 100 ml
4.8 Reagents for determination of lightweight contaminators (see 14.2)
4.8.1 Zinc chloride solution, obtained by dissolving 7 kg of ZnCl2 in 3 l of water to obtain a saturated
cooling to room temperature, shall be checked using a suitable hydrometer (5.9.3)
NOTE Zinc chloride solution is moderately irritating to skin and mucous membranes
4.8.2 Sodium polytungstate solution (as an alternative to 4.8.1), prepared by dissolving
cooling to room temperature, shall be checked using a suitable hydrometer (5.9.3)
4.9 Reagents for determination of potential presence of humus (see 15.1)
4.9.1 A 3 % solution of sodium hydroxide, made by dissolving 30 g of sodium hydroxide pellets in
water, cooling to room temperature and diluting to 1 l in a volumetric flask
4.9.2 Standard colour solution, prepared by dissolving 45,0 g of FeCl3.6H2O and 5,50 g of
Store the solution in a glass bottle
NOTE 1 The solution should be stable for at least two weeks
NOTE 2 The standard colour solution (tangerine-orange) is equivalent to Gardner Colour Standard Number°11 or Organic Plate Number°31)
4.10 Reagents for determination of fulvo acid content (see 15.2)
4.10.1 Hydrochloric acid, diluted (1 + 23) (4.1)
4.10.2 Stannous chloride solution, made by dissolving 22,5 g of SnCl2.2H2O in 1 l of hydrochloric acid (4.10.1)
NOTE The solution should be stable for at least two weeks
1) Colour scale discs and equivalent standard solutions can be obtained from:
Tintometer Ltd, Lovibond House, Solar Way, Solstice Park, Amesbury, Wiltshire, SPA 7SZ, UK
Tel: +44.1980.664800; Fax: +44.1980.625412; Email: sales@tintometer.com; website: www.tintometer.com
or
Intertest Benelux v.o.f P.O Box 373 NL - 4870 AJ Etten-Leur
Phone: +31 (0)76 501 53 51; Fax: +31 (0)76 503 31 81; Email: intertest@intertest.nl or info@intertest.nl; website:
www.intertest.nl
This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of the product named Equivalent products may be used if they can be shown to lead to the
Trang 164.11 Reagents for determination of free lime by complexometry (see 18.2)
4.11.1 Ethanediol (Ethylene glycol), fresh, anhydrous
4.11.2 Propan-2-ol (Isopropanol), anhydrous
4.11.3 Filter paper pulp, in anhydrous ethanediol
4.11.4 Hydrochloric acid, diluted (1+1) (4.1)
4.11.5 Triethanolamine
4.11.6 m-Nitrophenol (0,1 g in 100 ml H20)
4.11.7 Sodium hydroxide solution, 2 mol/l, made by dissolving 80 g of sodium hydroxide pellets in
water, cooling to room temperature and diluting to 1 l in a volumetric flask
4.11.8 Indicator, made by grinding together 1 g of murexide (ammonium purpurate) and 100 g NaCl
using a pestle and mortar
4.11.9 EDTA solution 1/112 mol/l, (3,3 ± 0,1) g of ethylenediaminetetra - acetic acid disodium salt,
dried to constant mass at 80 °C, dissolved in water and made up to 1 l This solution needs to be standardized against a solution of known calcium content (4.11.10)
4.11.10 Standard calcium solution (1 ml = 1 mg of calcium oxide) Dissolve (1,785 ± 0,001) g of pure
calcium carbonate (4.11.11) dried at (110 ± 5) °C in a slight excess of (1 + 4) hydrochloric acid Boil the solution to expel carbon dioxide, cover and cool to room temperature and dilute to 1 l with water in
a volumetric flask (5.3.6)
NOTE Commercially standardized solutions are available, for example (1,000 ± 0,002) g CaO/l
4.11.11 Calcium carbonate (CaCO3) precipitated grade, volumetric standard
4.11.12 Soda-lime, granulated
4.12 Reagent for determination of free lime by conductometry (see 18.3)
Ethanediol (4.11.1)
4.13 Reagents for determination of free lime by acidimetry (see 18.4)
4.13.1 Ethyl acetoacetate, anhydrous grade
4.13.2 2-methyl propan-l-ol, (isobutyl alcohol) anhydrous grade
4.13.3 Thymol blue indicator (thymolsulfonephthalein)
4.13.4 Hydrochloric acid, (4.1)
4.13.5 Solvent solution, 450 ml of ethyl acetoacetate in 3 l of 2-methylpropan-l-ol
4.13.6 Indicator, 0,1 g of thymol blue indicator powder dissolved in 100 ml of 2-methylpropan-l-ol 4.13.7 Hydrochloric acid solution approximately 0,2 mol/l
To prepare this solution, make up 17 ml of hydrochloric acid (4.1) to 1 l with 2-methylpropan-l-ol
Trang 17To standardize this solution, weigh (100 ± 0,1) mg of calcium carbonate (4.11.11) in a crucible (5.6.2) and calcine for 1 h at 1000 °C Extract the free lime and titrate in accordance with 18.4.3
Determine the k factor from the following equation:
V
k
409
,
100
100 08
NOTE The value of factor k for the solution should be calculated using the mean value of three
determinations, expressed to three decimal places
4.13.8 Sodium hydroxide on support granulated about 0,8 mm to 1,6 mm for elementary analysis
4.14 Reagent for the determination of the expansion of steel slag (see 19.3)
4.14.1 Silicone oil
4.14.2 Hydrochloric acid diluted (1 + 5)
5 Apparatus
5.1 General requirements
All apparatus shall comply with the general requirements of EN 932-5
Unless otherwise stated, all volumetric glassware shall be of class B accuracy as defined in ISO 384:1978 Volumetric glassware of class A accuracy shall be used for audit tests and for type tests
NOTE Where no tolerances are specified for dimensions, the values quoted are approximate
5.2 Apparatus for general purposes
5.2.1 Well ventilated oven, capable of being controlled to maintain a constant temperature in the
range of 40 °C to 150 °C with an accuracy of ± 5 °C, equipped with a heat resistant tray made of corrodible material
non-5.2.2 Electric muffle furnace capable of being controlled to maintain a constant temperature in the
range of 800 °C to 1 100 °C with an accuracy of ± 25 °C
5.2.3 Crushing and grinding equipment to reduce aggregates to sizes that pass through sieves
suitable for particular tests while producing a minimum of fines
5.2.4 Balance, capable of weighing up to 10 kg, readable to the nearest 1 g
5.2.5 Balance, capable of weighing up to 1 kg, readable to the nearest 0,01 g
5.2.6 Analytical balance, capable of weighing up to 100 g, readable to the nearest 0,1 mg
Trang 185.2.7 Hot plate with magnetic stirrer
5.2.8 pH meter, readable to 0,1 pH units
5.2.9 Beakers, conical flasks, funnels and filter paper
5.2.10 Pipettes, 25 ml, 50 ml and 100 ml, complying with the requirements of ISO 648
5.2.11 Graduated measuring cylinders, capacity 10 ml, 250 ml and 500 ml, complying with the
requirements of ISO 4788
5.2.12 Wash bottles, containing demineralized water
5.2.13 Burettes, 50 ml size, graduated to 0,1 ml, complying with the requirements of ISO 385
5.2.14 Amber-coloured glass reagent bottles
5.2.15 Plain glass reagent bottles
5.3.3 Mechanical shaker or roller, to take the extraction bottles (5.3.2)
5.3.4 Two filter funnels, of approximately 100 mm diameter with medium and fine grade filter
papers of a diameter appropriate to the size of the funnel
5.3.5 Stoppered conical flasks, 100 ml and 250 ml capacity
5.3.6 Two volumetric flasks, capacity of 1 l, complying with the requirements of ISO 1042
5.4 Additional apparatus required for potentiometric determination of water-soluble chloride salts (see Clause 8)
5.4.1 A potentiometric titrator suitable for the determination of chloride ion concentration with an
electrode system consisting of:
a) Measuring electrode - fitted with either a silver electrode (preferably chloridized) or a chloride ion - selective electrode
b) Reference electrode - either mercurous sulfate or a double junction silver/silver chloride with chloride free electrolyte in the outer chamber
Trang 195.5 Additional apparatus required for factory production control determination of water soluble chloride salts following Mohr (see Clause 9)
Two wide-mouthed plastic bottles of 1 l, with stoppers
5.6 Additional apparatus required for determination of water-soluble sulfates (see Clause 10)
5.6.1 Sintered silica filtering crucibles, porosity grade 4, approximately 35 mm in diameter and
40 mm in height
5.6.2 Ignition crucibles, as alternative to 5.6.1, approximately 35 mm in diameter and 40 mm in
height and capable of maintaining a constant mass when heated to 1 100 °C
NOTE Porcelain, silica or platinum are suitable materials for ignition crucibles
5.6.3 Spectrophotometer
NOTE The water-soluble sulfate content is obtained from the measured absorbance using a calibration graph This is established by dissolving known quantities of calcium sulfate in hot water and measuring the absorbance of the test solutions For this, the absorbance of at least five different solutions within the range 0 %
to 1.3 % sulfate should be determined The absorbance of the blank solution should always be established and deducted from the test solution
5.7 Additional apparatus required for the determination of total sulfur content (see Clause 11)
High temperature combustion apparatus, an induction furnace capable of reaching a temperature of
at least 2 000 ºC within a 40-second analysis period An appropriate accelerator should be used (for example, tungsten trioxide or vanadium pentoxide) Any evolved water vapour should be efficiently trapped
NOTE The apparatus should be calibrated regularly using standard materials, including aggregates of the type to be tested and pyrite The standards should cover the range of sulfur content expected If results outside this range are obtained, the machine should be recalibrated with appropriate standards and the test repeated Blanks should be run and if any sulfur is detected the machine should be cleaned until no sulfur is detected in the blanks
5.8 Additional apparatus required for determination of sulfide content (see
Clause 13)
Typical apparatus for the determination of sulfide content is shown in Figure 1
Trang 20Key
Figure 1 — Example of apparatus for the determination of sulfide
5.9 Additional apparatus required for determination of lightweight contaminators (see 14.2)
5.9.1 300 µm and 250 µm sieves complying with EN 933-2
5.9.2 Porcelain evaporating basin
5.9.3 Hydrometer, range 1,950 to 2,000, complying with the requirements of ISO 649-1
5.10 Additional apparatus required for determination of the potential presence of humus (see 15.1)
5.10.1 4 mm sieve, complying with EN 933-2
Trang 215.10.2 Clear, cylindrical glass bottle with stopper, with a capacity of approximately 450 ml and an
external diameter of approximately 70 mm
NOTE The approximate dimensions are intended to match a bottle that is commercially available A bottle of
a different size can affect the comparison with the standard colour
5.11 Additional apparatus required for determination of fulvo acid content (see 15.2)
5.11.1 Glass stirring rod
5.11.2 Glass filter funnel
5.11.3 180 mm diameter medium grade filter paper
5.11.4 Hot plate
5.12 Additional apparatus required for determination of organic contaminators by mortar method (see 15.3)
5.12.1 Stopwatch or a timer, readable to 1 s
5.12.2 Refractory porcelain or silica basins of size suitable for placing inside the muffle furnace 5.12.3 Plunger test apparatus conforming with the requirements of EN 1015-4
5.12.4 Mixer complying with the requirements of EN 196-1
5.12.5 Stiffening rate apparatus conforming with EN 1015-9
5.12.6 Flexural and compressive strength apparatus conforming to the requirements of EN 1015-11 5.12.7 Electric muffle furnace, with a capacity large enough for calcination of a 2 kg aggregate
portion, capable of maintaining a temperature of (480 ± 25) °C
5.13 Additional apparatus required for determination of free lime by complexometry (see 18.2)
5.13.1 Erlenmeyer flask, 250 ml capacity, with ground glass stopper
5.13.2 Volumetric flask, 500 ml capacity, complying with the requirements of ISO 1042
5.13.3 Magnetic stirrer with temperature controlled water bath
5.13.4 Sintered glass filter, 10 µm to 16 µm diameter of pores
5.13.5 Titration equipment with galvanometer for photoelectric end point determination
5.13.6 Test sieve, 63 µm woven wire cloth complying with the requirements of EN 933-2
5.14 Additional apparatus required for determination of free lime by conductometry (see 18.3)
5.14.1 Measuring vessel (volume approximately 160 ml) with a thermoplastic casing and screw cap
with two apertures with ground cone NS 14 as defined in DIN 12242-1:1980 (see Figure 2)
5.14.2 Conductive electrode with ground cone NS 14
Trang 225.14.3 Thermometer (50 °C to 100 °C): 0,1 °C graduated, with ground cone NS 14
5.14.4 Conductance meter
NOTE 1 The free lime content is obtained from the measured conductance using a calibration graph This is established by dissolving known quantities of calcined CaO in ethanediol and measuring the conductance of their solutions For this, the conductance of at least five different solutions within the range from 0 mg to 10 mg CaO/100 ml ethanediol (4.11.1) should be determined, in each case with three individual measurements
NOTE 2 The CaO used is produced by calcining CaCO3 (4.11.11) at 1 000 °C until it reaches a constant mass and then cooling in a desiccator which contains absorption materials for water and carbon dioxide, for example soda-lime
NOTE 3 The value of conductance of the blank solution of ethanediol should be established for each determination and deducted from the test solution
NOTE 4 Figure 3 shows the calibration of an ethanediol solution containing calcium oxide at 80 °C and an electrode constant of 0,573 cm-1 In this case, a measured conductance of 100 µS yields a value of 4,8 % (by mass) for the content of free lime
5.14.5 Water bath controllable to (80 ± 0,1) °C
5.14.6 Magnetic stirrer with temperature controlled water bath
Trang 245.15.1 Erlenmeyer flasks, 200 ml, 250 ml or 300 ml capacity, fitted with water-cooled condensers by
means of standard-taper inner joints
5.15.2 Absorption tubes to fit to the upper part of the condensers and containing the sodium
hydroxide (4.13.8) and the molecular sieve (5.15.3)
5.15.3 Molecular sieve 0,3 nm beads about 2 mm diameter
5.15.4 Glass microfibre filters of 1,2 mm retention
5.15.5 Equipment for vacuum filtration
5.15.6 Test sieve, 63 µm woven wire cloth complying with the requirements of EN 933-2
5.16 Additional apparatus required for the determination of CaO in steel slag by ray diffraction (see 18.5)
X-5.16.1 X-ray diffractometer
5.16.2 63 µm sieve complying with EN 932-2
Trang 255.17 Additional apparatus required for the determination of dicalcium silicate
disintegration of air-cooled blast-furnace slag (see 19.1)
5.17.1 Ultra-violet lighting equipment, of wavelength 300 nm to 400 nm with a maximum wavelength
intensity at 366 nm
5.18 Additional apparatus required for determination of the volume expansion of steel slag (see 19.3)
5.18.1 Steam unit with test cylinder and displacement indicator with a measuring range of
(10 ± 0,01) mm as shown in Figures 4, 5 and 6
NOTE The steam equipment consists of one or more chambers, in which water is heated up to boiling point over heating elements during the test Above the heating chamber is the compressed slag specimen in a cylinder with a perforated base, an internal diameter of about 210 mm and a height of about 120 mm The holes in the base allow steam to rise through the specimen evenly The water usage should be (1,1 ± 0,6) l/h To prevent condensation building up on the inside of the cylinder due to the heat loss, the cylinder is heated to (120 ± 10) °C
by a circular heating jacket fitted to the outside wall
Trang 26Key
5 Surcharge
Figure 5 — Cylinder with sample and loading/measuring equipment
Trang 27Dimensions in millimetres
Key
Figure 6 — Drill diagram of the cylinder base 5.18.2 Sieves, complying with EN 933-2, with mesh sizes 0,5 mm, 2,0 mm, 5,6 mm, 8,0 mm,
11,2 mm, 16,0 mm and 22,4 mm
5.18.3 Glass beads, diameter 5 mm
5.18.4 Medium grade filter paper, diameter 210 mm
5.18.5 Vibrating table, with an approximate frequency of (48 ± 3) Hz and an amplitude of ± 1,5 mm,
or another compacting devise which allows a final compaction of the test portion to a void content of (25 ± 3) % (by volume)
NOTE Other types of vibrating table, a Proctor hammer or a hand-held vibrating hammer may be suitable
5.18.6 Sounding rod graduated to the nearest mm, with a total scale length of 200 mm of more
Trang 285.18.7 Surcharge with an exterior diameter less than 210 mm (180 mm is typical) with a central hole
about 15 mm diameter to allow the stem of the displacement indicator to sit on top of the surcharge support, and to allow steam to escape The total combined mass of the surcharge, surcharge support and perforated plate shall be (6 ± 0,01) kg
6 General requirements for testing
6.1 Number of tests
Unless otherwise stated the number of single determinations of the various test methods (see Clauses 7 to 19) is fixed at two (see also 6.3)
6.2 Repeatability and reproducibility
The standard deviation of repeatability gives the closeness of agreement between successive results obtained with the same method on identical material tested under the same conditions (same operator, same apparatus, same laboratory and short time interval)
The standard deviation of reproducibility gives the closeness of agreement between individual results obtained with the same method on identical material but tested under different conditions (different operators, different apparatus, different laboratories and/or different times) (see EN 932-6)
The standard deviations of repeatability and reproducibility are expressed in absolute percentage Recognised values for some of the test methods are given in Annex A (informative)
NOTE The values of precision are taken from previous national standards or from cross-testing exercises recognised by CEN
6.3 Expression of mass, volume, factors and results
Record the mass from an analytical balance (5.2.6) in g to the nearest 0,1 mg and volume from the burettes (5.2.13) in ml to the nearest 0,05 ml
Record the mass from the ordinary balance specified in 5.2.4 in g to the nearest 1 g or from the balance specified in 5.2.5 to the nearest 0,01 g
Express the factors of solutions (4.7.5, 4.7.6 and 4.13.7), given by the mean of three determinations,
to three decimal places
Express the results of the tests, given by the mean of two determinations, as a percentage, to the nearest 0,01 %, unless otherwise stated
If an accepted value of repeatability is available (Annex A), the results for the two determinations shall
be reviewed If the difference between two determinations is more than twice the repeatability standard deviation, repeat the test and take the mean of the two closest values
6.4 Drying of materials
Unless otherwise stated in a test method, materials shall be dried in a well-ventilated oven (5.2.1), at a temperature of (110 ± 5) °C
Trang 296.5 Ignitions of precipitates
Ignite precipitates as follows:
Place the filter paper and its contents into a crucible, which has been previously ignited and tarred Dry and then incinerate the filter paper slowly in an oxidizing atmosphere without flaming, whilst ensuring complete combustion
Ignite the precipitate for at least 1 h at the stated temperature
Allow the crucible and its contents to cool to the room temperature in a desiccator Weigh the crucible and its contents
6.6 Check for the absence of chloride ions (silver nitrate test)
After five or six washes of a precipitate, rinse the base of the filter stem with a few drops of water
Wash the filter and its contents with several ml of water and collect this in a test tube Add several drops
of concentrated nitric acid (4.1) and of silver nitrate solution (4.2.1) Check for the absence of turbidity or precipitate in the solution If necessary, continue washing
The absence of turbidity in the silver nitrate test confirms that the washings are free from chloride ions
7 Determination of water-soluble chloride salts using the Volhard method (Reference method)
The chlorides are expressed in terms of, and reported as, the chloride ion content as a percentage by mass of the aggregate
NOTE With some aggregates, e.g from some desert areas, testing a nitric acid extract of the finely ground aggregate can show significantly higher levels of chloride than the water extraction method specified in this clause
7.2 Sampling
The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1
NOTE For marine aggregates the laboratory sample should be representative of the moisture content of the batch
7.3 Preparation of test specimens
Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the
mass given in Table 1, appropriate to the upper (D) sieve size of the aggregate
Dry the sub-sample at a temperature of (110 ± 5) °C to constant mass (3.4)
Trang 30Sieve the sub-sample through a 16 mm sieve (see 5.3.1) and crush any oversize samples to pass the sieve, avoiding excessive grinding Combine, mix thoroughly and using the procedures specified in
EN 932-2 produce two test specimens each with a mass of about (2 ± 0,3) kg for coarse aggregates or each with a mass of about (500 ± 75) g for fine aggregates
In the case of lightweight aggregates, the two test portions shall each have a volume of about 1 l
Table 1 — Minimum mass of preliminary sub-sample
Upper (D) sieve size of the
aggregate, mm
Minimum mass of sub-sample, kg
capacity (5.3.2) For fine aggregates use two bottles of 2 l capacity (5.3.2) Weigh each bottle and record its mass to the nearest 1 g
Transfer the test specimens (7.3) to the bottles Weigh the bottles and contents and record their mass
to the nearest 1 g Calculate the mass of aggregate in each bottle by difference
Add to each bottle a mass of water equal to the mass of the test specimen For lightweight aggregates add 1 l water
Agitate the bottles continuously for 60 min by means of the shaker or the roller (5.3.3)
Then filter the extracts through dry, medium grade filter papers (5.3.4) until at least 100 ml of clear or slightly opalescent filtrate has been collected in clean dry beakers (5.2.9)
7.5 Procedure for the determination of the chloride content of the extracts
Take 100 ml of the filtered extract (7.4) using a 100 ml pipette (5.2.10) and transfer to a 250 ml capacity flask (5.3.5) Add 5 ml of nitric acid (4.2.3) to the flask followed by silver nitrate solution (4.2.1) from a burette (5.2.13) until all the chloride has been precipitated and then add excess When aggregates containing sulfides (e.g slags) are being analysed, allow the solution to digest for
5 min at a temperature just below boiling A white precipitate of sulfur may form, but it is not necessary to filter this off Cool and add the silver nitrate solution
Add sufficient silver nitrate to ensure a titre of at least 3 ml of thiocyanate solution
Add 2 ml of 3,5,5-trimethylhexan-1-ol (4.2.4), stopper, and shake the flask vigorously to coagulate the precipitate
Carefully loosen the stopper, avoiding loss of solution and rinse the stopper with water, collecting the washings in the solution
Trang 31Add 5 ml of the ammonium iron (III) sulfate indicator solution (4.2.5) followed by the standardized thiocyanate solution (4.2.2) from a burette until the first permanent colour change occurs (from white opalescence to pale brown) and the solution has the same depth of colour as was used for the standardization specified in 4.2.2
Repeat the procedure with the extract from the second test specimen
The number of determinations on each extract is fixed at one
7.6 Calculation and expression of results
Calculate the chloride content C of aggregate from the following equation:
where
V5 is the volume of silver nitrate solution (in ml);
aggregate in g
NOTE A statement on the precision of the determination of water-soluble chlorides is given in Annex A
The result is given as the mean of the determination on the two extracts as a percentage, to the nearest 0,001 %
8 Determination of water-soluble chloride salts by potentiometry (Alternative method)
8.1 Principle
The aggregate test specimen is extracted in the same way as in 7.4 The chloride ions are precipitated from the extracts by means of a standard silver nitrate solution
The titration is executed by potentiometry, using a suitable electrode as indicator
NOTE Chloride ion selective electrodes and Gran's plot can also be used
8.2 Sampling, preparation of test specimens and extracts
Follow the procedures specified in 7.2, 7.3 and 7.4
8.3 Procedure for the determination of the chloride content of the extracts
Take 50 ml of the filtered extract (7.4) by means of the 50 ml pipette (5.2.10) and transfer to a 250 ml
chloride solution (4.3.2)
Trang 32When aggregates containing sulfides (e.g slags) are being analysed, allow the solution to digest for
5 min at a temperature just below boiling A white precipitate of sulfur may form, but it is not necessary
to filter this off Cool the contents of the beaker
By means of the potentiometric device (5.4.1), titrate with the silver nitrate solution (4.3.1) The chloride content of the solution is indicated by the consumption of silver nitrate solution relative to the point of inflection of the potential curve, the quantity of sodium chloride (4.3.2) added to improve end point recognition having been deducted
Repeat the procedure with the extract from the second test specimen
The amount of sodium chloride added shall be confirmed by a blank test
8.4 Calculation and expression of results
Calculate the chloride content C of aggregate from the following equation:
9.2 Principle
An aggregate test portion is rapidly extracted with water at room temperature to remove chloride ions The extract is then analysed by the method based on Mohr The chloride is titrated with silver nitrate using potassium chromate as an indicator The chloride ion concentration may also be determined using instrumental methods based on conductivity
9.3 Sampling
The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1
Trang 339.4 Preparation of test portion
Reduce the laboratory sample to a test portion with a mass of 250 g using the procedures specified in
EN 932-2 For lightweight aggregates, use a volume of 1 l
9.5 Preparation of extracts
For coarse and fine aggregates use two wide-mouthed plastic bottles of 1 l capacity (5.5) For lightweight aggregate use two bottles of 5 l capacity (5.3.2) Weigh each bottle and record its mass to the nearest 1 g
Transfer the test portion into the bottles Weigh each bottle with its contents and record the mass to the nearest 1 g Calculate the mass of aggregate in each bottle by difference
Add to each bottle a mass of water equal to the mass of aggregate For lightweight aggregate add 1 l
of water
Fasten the watertight bottle closures and mix the contents by shaking at least 20 times Allow to settle until the supernatant water is more or less clear
9.6 Procedure for the determination of the chloride content of the extracts
NOTE If conductivity measurement is being used, decant approximately 100 ml into a 250 ml beaker and measure the concentration
Take 25 ml of the supernatant water (9.5) using a 25 ml pipette (5.2.10) and transfer to a 100 ml capacity flask (5.3.5)
Add 4 ml to 6 ml of the potassium chromate solution (4.4) and mix Titrate by means of the 0,01 mol/l
silver nitrate solution (4.3.1) until light red Note the volume V8 of the silver nitrate solution used
9.7 Calculation and expression of results
Calculate the chloride content C of the aggregate from the following equation:
where
aggregate in g
10 Determination of water-soluble sulfates
10.1 Determination of water soluble sulfates in natural and manufactured
aggregates
10.1.1 Principle
An aggregate test specimen is extracted with water to remove soluble sulfate ions The soluble sulfate content is determined by precipitation at pH between 1 and 1,5 by a solution of barium chloride, at the boiling point