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BRITISH STANDARD

Tests for chemical properties of aggregates

Part 1: Chemical analysis

ICS 91.100.15

NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW

BS EN 1744-1:2009 +A1:2012

BS EN 1744-1:2009+A1:2012


National 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 It supersedes BS EN 1744-1:2009, which is withdrawn.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

ISBN 978 0 580 76567 4

Amendments/corrigenda issued since publication Date

Comments

31 January 2013

Implementation of CEN amendment A1:2012

EUROPEAN STANDARD

EN 1744-1:2009+A1

NORME EUROPÉENNE


EUROPÄISCHE NORM

November 2012

ICS 91.100.15

Supersedes EN 1744-1:2009

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 COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2012 CEN

All rights of exploitation in any form and by any means reserved worldwide for CEN national Members.

Ref. No. EN 1744-1:2009+A1:2012: E


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Contents

Page

Foreword ............................................................................................................................................................. 7 1

Scope...................................................................................................................................................... 8

2

Normative references ........................................................................................................................... 8

3

Terms and definitions ........................................................................................................................... 9

4 4.1 4.2

Reagents ................................................................................................................................................ 9 General ................................................................................................................................................... 9 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 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11 5.12 5.13 5.14

2

Apparatus ............................................................................................................................................ 15 General requirements ......................................................................................................................... 15 Apparatus for general purposes ....................................................................................................... 15 Additional apparatus required for determination of water-soluble chloride salts following Volhard (see Clause 7) ....................................................................................................... 16 Additional apparatus required for potentiometric determination of water-soluble chloride salts (see Clause 8) .............................................................................................................. 16 Additional apparatus required for factory production control determination of water soluble chloride salts following Mohr (see Clause 9) ........................................................... 17 Additional apparatus required for determination of water-soluble sulfates (see Clause 10) ............................................................................................................................................ 17 Additional apparatus required for the determination of total sulfur content (see Clause 11) ............................................................................................................................................ 17 Additional apparatus required for determination of sulfide content (see Clause 13) ................. 17 Additional apparatus required for determination of lightweight contaminators (see 14.2) .............................................................................................................................................. 18 Additional apparatus required for determination of the potential presence of humus (see 15.1) ................................................................................................................................. 18 Additional apparatus required for determination of fulvo acid content (see 15.2) ...................... 19 Additional apparatus required for determination of organic contaminators by mortar method (see 15.3) ................................................................................................................... 19 Additional apparatus required for determination of free lime by complexometry (see 18.2) .............................................................................................................................................. 19 Additional apparatus required for determination of free lime by conductometry (see 18.3) .............................................................................................................................................. 19

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

5.15 5.16


5.17 5.18

Additional apparatus required for acidimetric determination of free lime (see 18.4) .................. 22 Additional apparatus required for the determination of CaO in steel slag by X-ray diffraction (see 18.5). .......................................................................................................................... 22 Additional apparatus required for the determination of dicalcium silicate disintegration of air-cooled blast-furnace slag (see 19.1) .............................................................. 23 Additional apparatus required for determination of the volume expansion of steel slag (see 19.3) ...................................................................................................................................... 23

6 6.1 6.2 6.3 6.4 6.5 6.6

General requirements for testing ...................................................................................................... 26 Number of tests ................................................................................................................................... 26 Repeatability and reproducibility ...................................................................................................... 26 Expression of mass, volume, factors and results ........................................................................... 26 Drying of materials.............................................................................................................................. 26 Ignitions of precipitates...................................................................................................................... 27 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 Principle ............................................................................................................................................... 27 Sampling .............................................................................................................................................. 27 Preparation of test specimens ........................................................................................................... 27 Preparation of extracts ....................................................................................................................... 28 Procedure for the determination of the chloride content of the extracts ..................................... 28 Calculation and expression of results .............................................................................................. 29

7.1 7.2 7.3 7.4 7.5 7.6 8 8.1 8.2 8.3 8.4 9 9.1 9.2 9.3 9.4 9.5 9.6 9.7

Determination of water-soluble chloride salts by potentiometry (Alternative method) ................................................................................................................................................ 29 Principle ............................................................................................................................................... 29 Sampling, preparation of test specimens and extracts .................................................................. 29 Procedure for the determination of the chloride content of the extracts ..................................... 29 Calculation and expression of results .............................................................................................. 30 Determination of water-soluble chloride salts using the Mohr method (Alternative method) ................................................................................................................................................ 30 General ................................................................................................................................................. 30 Principle ............................................................................................................................................... 30 Sampling .............................................................................................................................................. 30 Preparation of test portion ................................................................................................................. 31 Preparation of extracts ....................................................................................................................... 31 Procedure for the determination of the chloride content of the extracts ..................................... 31 Calculation and expression of results .............................................................................................. 31

10 10.1 10.1.1 10.1.2 10.1.3 10.1.4 10.1.5 10.1.6 10.2 10.2.1 10.2.2 10.2.3 10.2.4 10.2.5

Determination of water-soluble sulfates........................................................................................... 31 Determination of water soluble sulfates in natural and manufactured aggregates ..................... 31 Principle ............................................................................................................................................... 31 Sampling .............................................................................................................................................. 32 Preparation of test portion ................................................................................................................. 32 Preparation of extracts ....................................................................................................................... 32 Procedure for the determination of the sulfate content of the extracts ........................................ 32 Calculation and expression of results .............................................................................................. 33 Determination of water soluble sulfates in recycled aggregates .................................................. 33 Principle ............................................................................................................................................... 33 Sampling .............................................................................................................................................. 33 Preparation of test specimen ............................................................................................................. 34 Preparation of extracts ....................................................................................................................... 34 Procedure for the determination of the sulfate content of the extracts, using a spectrophotometer ............................................................................................................................. 34

11 11.1 11.2

Determination of total sulfur content ................................................................................................ 35 Determination of total sulfur content by acid digestion (Reference method) .............................. 35 Determination of total sulfur content by high temperature combustion (Alternative method) ................................................................................................................................................ 37

3


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

11.2.1 11.2.2 11.2.3 11.2.4 11.2.5

Principle ............................................................................................................................................... 37 Sampling .............................................................................................................................................. 37 Preparation of test portion ................................................................................................................. 37 Procedure ............................................................................................................................................ 37 Calculation and expression of results .............................................................................................. 37

12 12.1 12.2 12.3 12.4 12.5

Determination of acid soluble sulfates ............................................................................................. 37 Principle ............................................................................................................................................... 37 Sampling .............................................................................................................................................. 38 Preparation of test portion ................................................................................................................. 38 Procedure ............................................................................................................................................ 38 Calculation and expression of results .............................................................................................. 38

13 13.1 13.2 13.3 13.4 13.5

Determination of acid soluble sulfides ............................................................................................. 39 Principle ............................................................................................................................................... 39 Sampling .............................................................................................................................................. 39 Preparation of test portion ................................................................................................................. 39 Procedure ............................................................................................................................................ 39 Calculation and expression of results .............................................................................................. 40

14 14.1 14.1.1 14.1.2 14.1.3 14.2 14.2.1 14.2.2 14.2.3 14.2.4

Determination of components affecting the surface finish of concrete ....................................... 40 Examination for the presence of reactive iron sulfide particles .................................................... 40 General ................................................................................................................................................. 40 Sampling .............................................................................................................................................. 40 Procedure ............................................................................................................................................ 41 Determination of lightweight contaminators ................................................................................... 41 General ................................................................................................................................................. 41 Principle ............................................................................................................................................... 41 Procedure ............................................................................................................................................ 41 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 16.1 16.1.1 16.1.2 16.1.3

4

Determination of water solubility ...................................................................................................... 47 Determination of water solubility of aggregate, excluding filler .................................................... 47 Principle ............................................................................................................................................... 47 Sampling .............................................................................................................................................. 47 Preparation of test portion ................................................................................................................. 47


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

16.1.4 16.1.5 16.2 16.2.1 16.2.2 16.2.3 16.2.4 16.2.5

Extraction of soluble components .................................................................................................... 47 Calculation and expression of results .............................................................................................. 47 Determination of water solubility of filler ......................................................................................... 48 Principle ............................................................................................................................................... 48 Sampling .............................................................................................................................................. 48 Preparation of test portion ................................................................................................................. 48 Extraction of soluble component ...................................................................................................... 48 Calculation and expression of results .............................................................................................. 48

17 17.1 17.2 17.3 17.4

Determination of loss on ignition ...................................................................................................... 49 Principle ............................................................................................................................................... 49 Sampling and preparation of test portion ........................................................................................ 49 Procedure for the determination of loss on ignition ....................................................................... 49 Calculation and expression of results .............................................................................................. 49

18 18.1 18.2 18.2.1 18.2.2 18.2.3 18.2.4 18.3 18.3.1 18.3.2 18.3.3 18.3.4 18.4 18.4.1 18.4.2 18.4.3 18.4.4 18.5 18.5.1 18.5.2 18.5.3 18.5.4

Determination of free lime in steel slag ............................................................................................ 50 General ................................................................................................................................................. 50 Determination of free lime by complexometry (Reference method) .............................................. 50 Principle ............................................................................................................................................... 50 Sampling and preparation of test portion ........................................................................................ 50 Procedure ............................................................................................................................................ 50 Calculation and expression of results .............................................................................................. 51 Determination of free lime by conductometry (Alternative method) ............................................. 51 Principle ............................................................................................................................................... 51 Sampling and preparation of test portion ........................................................................................ 51 Procedure ............................................................................................................................................ 51 Evaluation and expression of results ............................................................................................... 51 Determination of free lime by acidimetry (Alternative method) ..................................................... 51 Principle ............................................................................................................................................... 51 Sampling and preparation of test portion ........................................................................................ 52 Procedure ............................................................................................................................................ 52 Calculation and expression of results .............................................................................................. 52 Determination of CaO in steel slag by X-ray diffraction ................................................................. 52 Principle ............................................................................................................................................... 52 Procedure of analysis ......................................................................................................................... 53 Calibration procedure ......................................................................................................................... 54 Analytical results ................................................................................................................................ 55

19 19.1 19.1.1 19.1.2 19.1.3 19.1.4 19.1.5 19.1.6 19.2 19.2.1 19.2.2 19.2.3 19.2.4 19.2.5 19.3 19.3.1 19.3.2 19.3.3 19.3.4 19.3.5 19.3.6

Determination of unsoundness of blast-furnace and steel slags .................................................. 55 Determination of dicalcium silicate disintegration of air-cooled blast-furnace slag ................... 55 General ................................................................................................................................................. 55 Principle ............................................................................................................................................... 55 Sampling .............................................................................................................................................. 55 Preparation of test portion ................................................................................................................. 55 Procedure ............................................................................................................................................ 55 Expression of results.......................................................................................................................... 55 Determination of iron disintegration of air-cooled blast-furnace slag .......................................... 56 General ................................................................................................................................................. 56 Principle ............................................................................................................................................... 56 Sampling .............................................................................................................................................. 56 Procedure ............................................................................................................................................ 56 Expression of results.......................................................................................................................... 56 Determination of the expansion of steel slag .................................................................................. 56 General ................................................................................................................................................. 56 Principle ............................................................................................................................................... 56 Sampling .............................................................................................................................................. 56 Preparation and compaction of the specimens ............................................................................... 56 Steam test procedure ......................................................................................................................... 58 Calculation and expression of results .............................................................................................. 58

Annex A (informative) Precision ..................................................................................................................... 60

5

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

A.1 A.2


A.3 A.4 A.5 A.6

Symbols ............................................................................................................................................... 60 Determination of water-soluble chloride salts using the Volhard method (Reference method) (See Clause 7)................................................................................................... 60 Determination of water-soluble chloride salts by potentiometry (Alternative method) (See Clause 8) ...................................................................................................................... 60 Determination of water-soluble sulfates in recycled aggregate (See 10.2) .................................. 60 Determination of total sulfur content by acid digestion (Reference method) (See 11.1) ...................................................................................................................................................... 60 Determination of acid soluble sulfates (See Clause 12) ................................................................. 61

Bibliography ..................................................................................................................................................... 62

6


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Foreword 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: 

Part 3: Preparation of eluates by leaching of aggregates



Part 4: Determination of water susceptibility of fillers for bituminous mixtures



Part 5: Determination of acid soluble chloride salts



Part 6: Determination of the influence of recycled aggregate extract on the initial setting time of 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.

7

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


1

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

8

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

ISO 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. 3.1 test portion subsample used as a whole in a single test 3.2 test specimen sample used in a single determination when a test method requires more than one determination of a property 3.3 laboratory sample sample intended for laboratory testing 3.4 constant mass 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 predetermined 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.

4 4.1

Reagents 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.

9

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


4.1.2

Concentrated liquid reagents shall have the following densities in g/cm³ at 20 °C:

Hydrochloric acid

: 1,18 to 1,19

Nitric acid

: 1,39 to 1,42

Sulfuric acid

: 1,84

Ammonium hydroxide

: 0,88 to 0,91

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 cT, (in mol/l), from the following equation: cT = 2,5/V1

(1)

where V1 is the volume of thiocyanate added (in ml). 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).

10

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


4.3 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) Potassium chromate (K2CrO4) solution, prepared by dissolving 10 g of potassium chromate in 100 ml 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 (Pb(CH3COO)2.3H2O) in water and making up to 100 ml. 4.7.2 Ammoniacal zinc sulfate solution, made by dissolving 50 g of zinc sulfate (ZnSO4.7H2O) in 150 ml water and add 350 ml of concentrated ammonium hydroxide (NH4OH). Leave to stand for at 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 potassium iodate (KIO3) dried at (110 ± 5) °C, two pellets (about 0,4 g) of sodium hydroxide (NaOH) 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:

F=

m1 3,566 8

(2)

11

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

where


m1

is the mass of the portion of potassium iodate in g.

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:

f =

20 × 0,016 67 × 214,01 × F F = 20 × 3,566 8 × V2 V2

(3)

where F

is the factor of the standard potassium iodate solution (4.7.5) expressed in mol/l;

V2

is the volume of the approximately 0,1 mol/l sodium thiosulfate solution used for the titration.

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:

f =

m 1 000 × m2 = 280,363 4 × 2 3,566 8 × V 3 V3

where m2

12

is the mass of the portion of potassium iodate in g;

(4)

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

V3

is the volume of the approximately 0,1 mol/l sodium thiosulfate solution used for the titration.


NOTE 2 iodate.

3,566 8 g/l of potassium iodate corresponds to a solution with exactly 0,016 67 mol/l of potassium

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 3 solution of density of (1,98 ± 0,02) g/cm at (20 ± 3) °C. The relative density of the solution, after 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 3Na2WO4.9W03.H2O crystals in water until the density of well stirred solution containing no 3 undissolved crystals is (1,98 ± 0,02) g/cm at (20 ± 3) °C. The relative density of the solution, after 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 CoCl2.6H2O in 279,5 g of water with 1 ml concentrated HCl. 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: [email protected]; 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: [email protected] or [email protected]; 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 same results.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

4.11 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 4.13.1

Reagents for determination of free lime by acidimetry (see 18.4) 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.

14

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

To 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:

k=

56,08 × 100 100,09 × V 4

(5)

where V4

is the volume of hydrochloric acid added (in ml);

k

represents the number of mg of free CaO per ml of standardized hydrochloric acid solution.

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

5.2

Where no tolerances are specified for dimensions, the values quoted are approximate.

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 noncorrodible material. 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.

15


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

5.2.7

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. 5.2.16 Desiccators. 5.2.17 Fume cupboard. 5.2.18 Watch glass.

5.3 Additional apparatus required for determination of water-soluble chloride salts following Volhard (see Clause 7) 5.3.1

Test sieve, 16 mm square hole perforated plate complying with the requirements of EN 933-2.

5.3.2 Two glass, plastic or metal bottles, or wide-mouthed Erlenmeyer flasks, with well fitting stoppers. NOTE The bottles should be approximately 5 l capacity when testing coarse aggregates or lightweight aggregates; approximately 2 l capacity when testing fine aggregates; and 300 ml Erlenmeyer flasks for testing filler.

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.

16

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

5.5 Additional apparatus required for factory production control determination of water soluble chloride salts following Mohr (see Clause 9) Licensed to Mr George Calvar on 26 May 2015. 1 user personal license only. Copying, copy/pasting, storage & distribution or use on network prohibited. (10530313). Get permission to copy from or network this publication www.saiglobal.com/licensing

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

5.6.3

Porcelain, silica or platinum are suitable materials for ignition crucibles.

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.

17


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Key 1

Lead acetate solution (4.7.1)

3

Ammoniacal solution of zinc sulfate (4.7.2)

2

Nitrogen or argon

4

Reaction flask

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.

18

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


5.10.2 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.

19

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

5.14.3 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 -1 electrode constant of 0,573 cm . 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.

20


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Key 1

Thermometer (5.14.3)

2

Electrode (5.14.2)

3

Polypropylene cap

4

Vessel made of borosilicate glass

5

Plastic casing

6

Water inlet

7

Magnetic stirrer (5.14.6) Figure 2 — Vertical section of a measuring vessel for determination of free lime by conductometry (5.14 and 18.3)

21


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Key 1 = 0 mg to 10 mg weighed in 100 ml ethanediol. Measuring temperature (80 ± 0,1) °C. Electrode -1 constant 0,573 cm . X = Calcium oxide content of ethanediol solution in mg CaO/100 ml. Y = Conductance in µS. Figure 3 — Example of a calibration graph 5.14.7 Test sieve, 63 µm woven wire cloth complying with the requirements of EN 933-2.

5.15 Additional apparatus required for acidimetric determination of free lime (see 18.4) 5.15.1 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 Xray diffraction (see 18.5). 5.16.1 X-ray diffractometer. 5.16.2 63 µm sieve complying with EN 932-2.

22

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


5.17 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.

Key 1

Test cylinder

2

Water gauge

3

Displacement indicator

4

Slag specimen

5

Heating jacket

6

Perforated base

7

Steam

8

Water

9

Heating coil

Figure 4 — Vertical section of a typical steam test equipment with two chambers

23


BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Key 1

Cylinder with perforated base, 49 holes, 3 mm diameter, distributed as given in Figure 6

2

Fabric mat

3

Compacted slag specimen

4

Glass beads, 5 mm diameter

5

Surcharge

6

Displacement indicator

7

Surcharge support, allowing steam to pass

8

Perforated plate, (30 ± 5) % open area Figure 5 — Cylinder with sample and loading/measuring equipment

24

BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


Dimensions in millimetres

Key Central point:

1 hole

st

1 circle, 65 mm diameter:

8 holes

nd

16 holes

rd

24 holes

2 circle, 125 mm diameter: 3 circle, 185 mm diameter:

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.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


5.18.7 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 6.1

General requirements for testing 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.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

6.5

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) 7.1

Principle

This test is suitable for aggregates where the chloride content derives directly from contact with, or immersion in, saline water, e.g. typical sea-dredged aggregates. An aggregate test specimen is extracted with water to remove chloride ions. The method of analysis of the extract is based on that of Volhard titration where an excess of silver nitrate solution is added to the chloride solution and the unreacted portion is back titrated with a standardized solution of thiocyanate, using ammonium iron (III) sulfate solution as an indicator. 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 batch.

7.3

For marine aggregates the laboratory sample should be representative of the moisture content of the

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).

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Sieve 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

7.4

Minimum mass of sub-sample, kg

63

50

45

35

31,5

15

22,4 or less

5

Preparation of extracts

For coarse aggregates and lightweight aggregates, use two wide-mouthed bottles of 5 l 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. Record the total volume V5 of silver nitrate solution added. 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.

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Add 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. Record the volume V6 of the thiocyanate solution added. 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: C = 0,003 546 W {V5 - (10 cT V6)}

(in %)

(6)

where V5

is the volume of silver nitrate solution (in ml);

V6

is the volume of standardized thiocyanate solution added (in ml);

cT

is the concentration of the standardized thiocyanate solution (in mol/l);

W

is the water aggregate ratio (in g/g) - for lightweight aggregates; W is 1 000 g/mass of the 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

8.2

Chloride ion selective electrodes and Gran's plot can also be used.

Sampling, preparation of test specimens and extracts

Follow the procedures specified in 7.2, 7.3 and 7.4.

8.3


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 beaker. Acidify with nitric acid (HNO3) (4.2.3) to a pH value of 2 to 3. Add by pipette 5 ml of sodium chloride solution (4.3.2).

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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 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


Calculate the chloride content C of aggregate from the following equation: C = 0,000 709 V7 W (in %)

(7)

where V7

is the consumption of silver nitrate solution, in ml, subtracting 10 ml for the added chloride solution;

W


The result is given as the mean of the determination on the two extracts as a percentage of the nearest 0,001 %. NOTE A statement on the precision of the determination of water-soluble chlorides by potentiometry is given in Annex A.

9 Determination of water-soluble chloride salts using the Mohr method (Alternative method) 9.1

General

The chloride ion concentration of the aqueous extract of natural aggregate may be determined using instrumental techniques based on conductivity measurement. This test method gives a more rapid method of extraction than the one specified in Clause 7. It is strongly recommended that this procedure is used as a preliminary check before using the test specified in Clause 7 to confirm compliance with a specification, if necessary. This procedure shall only be used for factory production control.

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.

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9.4

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


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


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


Calculate the chloride content C of the aggregate from the following equation: C = 0,01 0,0354 5 V8 W 4 (in %)

(8)

where V8

is the used volume of 0,01 mol/l silver nitrate solution;

W


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 water-soluble sulfate ions. The watersoluble sulfate content is determined by precipitation at pH between 1 and 1,5 by a solution of barium chloride, at the boiling point.

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The determination is then completed gravimetrically and the sulfate ion content is expressed as a percentage by mass of the aggregate.


This method is applicable when aggregates containing sulfides, e.g. slags, are being analysed. 10.1.2

Sampling

The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. 10.1.3


Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass given in Table 1 (7.3) 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). Sieve the sub-sample through a 16 mm sieve (see 5.3.1). Crush any oversize particles 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 specimens shall have a volume of about 1 l. 10.1.4


For coarse or lightweight aggregates use two plastic or metal bottles of 5 l capacity and for fine aggregate 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 obtained as specified in 10.1.3 to the bottles. Weigh each bottle and 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 twice the mass of the test specimen. For lightweight aggregate, add 1 l of water. Fasten the watertight bottle closures and mix the contents by shaking or rolling (5.3.3) continuously for a minimum of 24 h. NOTE If mechanical agitation equipment is not used and the aggregate and water are merely left in contact with occasional shaking there is a possibility (particularly if the source of sulfate is, for example, large crystals of gypsum) that all of the soluble sulfate will not be extracted in 24 h.

Filter the extracts through dry, medium-grade filter papers (5.3.4) until at least 100 ml of clear filtrates have been collected in clean dry beakers (5.2.9). 10.1.5

Procedure for the determination of the sulfate content of the extracts

With a pipette (5.2.10), transfer 50 ml of filtered extract to a 500 ml beaker. Dilute to 300 ml with water and add 10 ml of hydrochloric acid solution (4.5.1). Bring to the boil and boil for 5 min. NOTE 1 If the aggregate contains sulfides, e.g. slags, after boiling for 5 min, stand the solution in a warm place for 30 min. If a white precipitate forms, filter through a medium grade filter paper and wash thoroughly with hot distilled water. Discard the residue and continue as below.

While stirring vigorously and maintaining the solution at boiling point, add drop-by-drop 5 ml of the barium chloride solution (4.5.2) heated to just below boiling. Continue boiling for 15 min so that a precipitate is properly formed.

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Stand just below boiling for 30 min then leave in a warm place overnight. Transfer the precipitate of barium sulfate with care to a previously ignited and weighed sintered silica filter crucible (5.6.1) using suction. Alternatively transfer the precipitate with care to a fine filter paper in a glass funnel and filter. In either case wash the precipitate several times with hot water until the washings are free from chloride (6.6). If a sintered silica filter crucible is used, remove it from the filter flask and dry at (110 ± 5) °C for approximately 30 min and gradually raise the temperature to (925 ± 25) °C in an electric muffle furnace (5.2.2) until no further loss in mass occurs. NOTE 2

15 min at the higher temperature should suffice.

Cool the crucible in a desiccator (5.2.16) and weigh to the nearest 0,1 mg. Calculate the mass of the precipitate m3 from the increase in mass of the crucible. If the precipitate is filtered through a filter paper, transfer the filter paper and precipitate to a previously ignited and weighed crucible (5.6.2). Place the crucible and contents in the electric muffle furnace (5.2.2) following the procedure specified in 6.5. Cool the crucible in a desiccator (5.2.16) and weigh to the nearest 0,1 mg. Calculate the mass of the precipitate m3 from the increase in mass of the crucible. 10.1.6


Calculate the soluble sulfate content of the aggregate, expressed as SO3, from the following equation: Soluble SO3 = 2 W 0,343 m3 (in %)

(9)

where m3

is the mass of the precipitate of barium sulfate in g;

W


NOTE

Results can be expressed in SO4 using the following equation: Soluble SO4 = 2 W 0,4116 m3 (in %)

10.2 10.2.1

Determination of water soluble sulfates in recycled aggregates Principle

An aggregate test specimen is mixed with hot water to extract water-soluble sulfate ions. Barium chloride is then added to the extract, buffered at neutral pH, so that sulfate ions precipitate as barium sulfate. The water-soluble sulfate content is then determined by spectrophotomery. The extraction with hot water removes active sulfates (e.g. gypsum plaster) which are potential sources of unsoundness in the aggregate. 10.2.2

Sampling

The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. It shall have a mass of at least 3 000 g.

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10.2.3

Preparation of test specimen


Sieve the laboratory sample through a 4 mm sieve and crush any oversize to pass 4 mm sieve. Reduce to a test specimen of about (25 ± 0,1) g. Weigh the test specimen to the nearest 0,1 g in a 2 l beaker marked as "A" (5.2.9). 10.2.4 Preparation of extracts Weigh (1 000 ± 5) g distilled or demineralized water previously heated at (60 ± 5) °C in a 1 l or 2 l beaker (5.2.9). Immediately add the heated water to the test portion in beaker "A" (10.2.3). Cover the beaker with a watch glass (5.2.18). Stir content of beaker for (15 ± 1) min with a magnetic stirrer, whilst maintaining a temperature of (60 ± 5) °C. Immediately filter (200 ± 50) ml of the extract solution through a rapid filter into a 500 ml beaker marked as "B". Filter the remainder of the solution and retain it in a third beaker marked as "C". NOTE

The contents of beaker C may be used later for a dilution (10.2.5.3).

Buffer the filtered solution in beaker B with tartaric acid or nitric acid to obtain a pH value of 7 ± 1. Check the pH value of the solution using pH meter (5.2.8). If the pH value becomes too acid (below 6), add a little of the retained extract from beaker C to return it to neutrality. Cover the buffered solution in beaker B and the retained solution in beaker C with a watch glass. If necessary, allow them to cool. 10.2.5 Procedure for the determination of the sulfate content of the extracts, using a spectrophotometer 10.2.5.1

Blank test on the water

Before each series of determinations, check the sulfate content of the distilled or demineralized water. Follow the procedures outlined for the determination specified in 10.2.5.3. Take the indicated quantity of distilled or demineralized water using a pipette and pour it into a test tube. Add the specified amount of barium chloride solution (4.5.2) and let it stand for the indicated resting time. Vigorously shake the test tube for 10 s and read the spectrophotometer result. The result should normally be 0 mg/l. If it is not, record the result as CH2O. 10.2.5.2

Blank test on the solution

Before each determination carry out a blank test using the procedure in 10.2.5.3, but without adding barium chloride. Take the indicated quantity of buffered solution from beaker B using a pipette and pour it into a suitable test tube. After the indicated resting time for the apparatus, record the result as C0.

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10.2.5.3

Procedure for the determination of sulfate content


Take the quantity of buffered solution indicated by the manufacturer from beaker B using a pipette and pour it into a test tube or apparatus tank. Add the specified amount of barium chloride solution (4.5.2), as indicated by the manufacturer. Vigorously shake the test tube for 30 s and leave it during for the resting time recommended in the manufacturer’s instructions (usually 5 min to 10 min). Vigorously shake the test tube again for 10 s to put any crystals of BaSO4 deposited on the base of the test tube into suspension. Allow to stand for 15 s to allow any air bubbles to disperse and record the spectrophotometer result as CSO4 in mg/l. If the result exceeds 200 mg/l, repeat the operation with a diluted test portion. Use a pipette to transfer 50 ml of buffered solution from beaker B to another beaker marked as "D". Use another pipette to add 50 ml of distilled or demineralized water to beaker D. Stir for 1 min with a magnetic stirrer. Repeat the determination described in 10.2.5.3 using the diluted solution and make appropriate adjustments when calculating the results. 10.2.5.4


Calculate the soluble sulfate SO4 content of the recycled aggregate from the following equation: T SO4 = [((CSO4 – C0)/10 000) P/P’] – CH2O ≅ (CSO4 – C0)/250

(10)

where T SO4

is the water-soluble sulfate content of the sample, in %;

CSO4

is the spectrophotometer result (10.2.5.3);

C0

is the spectrophotometer result for the blank test (10.2.5.2);

CH2O

is the spectrophotometer result for the water test (10.2.5.1);

P

is the mass of water in grams (g) used for leaching the sample (10.2.4);

P’

is the mass, in grams (g) of the test portion (10.2.3).

11 11.1

Determination of total sulfur content Determination of total sulfur content by acid digestion (Reference method)

! 11.1.1 Principle An aggregate test specimen is treated with hydrogen peroxide and hydrochloric acid to convert any sulfur compounds present to sulfates. Any sulfates are precipitated as barium sulfate (BaSO4) and weighed. The sulfur content is expressed as a percentage by mass of the aggregate.

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11.1.2 Sampling The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. The laboratory sample should be representative of the moisture content of the batch. 11.1.3 Preparation of test portion Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 appropriate to the upper (D) sieve size of the aggregate. If necessary, dry the sample at a temperature of (110 ± 5) °C. NOTE

Drying at a higher temperature will oxidise any sulfides.

Stepwise crush and reduce the sub-sample to a mass of approximately 20 g and then grind the particles until they all pass the 125 µm sieve. Take approximately 1 g of this material as the test portion. 11.1.4 Procedure Weigh the test portion to the nearest 0,1 mg (m4) into a 400 ml high form beaker (5.2.9). Add 20 ml distilled water to elutriate, using a glass rod and watch glass. In the fume cupboard, add 10 ml of hydrogen peroxide (4.6.1) and warm for 30 min below the boiling point. After the dissolution, add 20 ml hydrochloric acid (1+1) (4.1) and leave the test specimen in a heat bath for 30 min. Add a small amount of filter paper pulp and warm up the content of the beaker to below the boiling point. Make the solution alkaline by adding ammonium hydroxide (4.1). Check the alkalinity by using methyl red as an indicator (4.6.2), or by using a pH-meter (5.2.8). Simmer for 30 s and then filter under gentle suction using a medium porosity filter paper. Wash the contents of the filter once with a little hot, demineralized water and reserve the filtrates. Transfer the paper filter and the particles retained on it into the beaker and dissolve in 5 ml concentrated hydrochloric acid (4.1) to which has been added 70 ml hot water. Repeat the procedure above (boil, precipitate, filter and wash) and reject the precipitate if any. Acidify the combined filtrates and washings (which should be about 220 ml in all) with 1 ml concentrated hydrochloric acid and bring it to the boil. Boil for (5 ± 0,5) min. While maintaining the solution at boiling point and stirring vigorously, add drop-by-drop 10 ml of the barium chloride solution (4.5.2) heated to just below boiling. Mature, filter and ignite the barium sulfate precipitate as specified in 10.1.5. Weigh to the nearest 0,1 mg and calculate the mass of precipitate m5. 11.1.5 Calculation and expression of results Calculate the total sulfur content of the aggregate, expressed as S to the nearest 0,1%, from the following formula: S = m5/m4 × 13,74 (in %) where

36

(11)


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NOTE

m5

is the mass of precipitate in grams;

m4

is the mass of the test portion in grams.

A statement on the precision of the determination of total sulfur content is given in Annex A."

11.2 Determination of total sulfur content by high temperature combustion (Alternative method) 11.2.1

Principle

An aggregate test portion is ignited at high temperature in an atmosphere of pure oxygen. This converts any sulfur compounds present into sulfur dioxide which is quantified by infrared detectors. The sulfur content is expressed as a percentage by mass of the aggregate. 11.2.2

Sampling

The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. NOTE

11.2.3

The laboratory sample should be representative of the moisture content of the batch.


Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 (7.3) appropriate to the upper (D) sieve size of the aggregate. If necessary, dry the sample at a temperature of (110 ± 5) °C. NOTE


Stepwise crush and reduce the sub-sample to a mass of approximately 20 g and then grind the particles until they all pass the 125 µm sieve. Take approximately 1 g of this material as the test specimen. 11.2.4

Procedure

The test portion shall be tested using an appropriate high temperature combustion apparatus (5.7) in accordance with the manufacturer's instructions. The total sulfur content is obtained directly from the readout of the apparatus. 11.2.5


The results should be presented as S, to the nearest 0,1 %.

12

Determination of acid soluble sulfates

!

12.1 Principle Sulfates are extracted from a test portion of the aggregate by dilute hydrochloric acid. The sulfate ion content is determined by gravimetry and expressed as a percentage by mass of the aggregate.

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12.2 Sampling The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. The laboratory sample should be representative of the moisture content of the batch.

12.3 Preparation of test portion Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 appropriate to the upper (D) sieve size of the aggregate. If necessary, dry the sample at a temperature of (110 ± 5) °C. NOTE


Stepwise crush and reduce the sub-sample to a mass of approximately 20 g and then grind the particles until they all pass the 125 µm sieve. Take approximately 8 g of this material as the test portion.

12.4 Procedure Weigh the test portion to the nearest 0,1 mg (m6). Place 360 ml water and 40 ml of concentrated hydrochloric acid (4.1) in a 1000 ml conical flask (5.2.9) and heat to boiling point. Remove from the source of heat and, while stirring, sprinkle the test portion on to the acid solution. Break up the solids with the flattened end of a glass-stirring rod. Allow the solution to digest for (15 ±1) min at a temperature just below boiling. Filter the residue through a medium filter paper into a 1000 ml beaker. Thoroughly wash the contents of the filter with hot demineralized water. Check the washings to ensure the absence of chloride ions using the silver nitrate test (6.6). Adjust the volume to about 600 ml with demineralized water and warm up the content of the beaker to below the boiling point. Make the solution alkaline by adding ammonium hydroxide solution (4.1.2). Check the alkalinity by using methyl red as an indicator (4.6.2), or by using a pH-meter (5.2.8). Simmer for 30 s and then filter under gentle suction using a medium porosity filter paper. Wash the contents of the filter at least 3 times with a little hot, demineralised water, reserve the filtrates and reject the precipitate if any. Acidify the filtrates and washings by means of hydrochloric acid (1+11) to red coloration of methyl red indicator (4.6.2). Bring to the boil and boil for (5 ± 0,5) min and then check that the solution is clear. If it is not clear, start the test again using a new test portion. While maintaining the solution at boiling point and stirring vigorously, slowly add 40 ml of the barium chloride solution (4.5.2) heated to just below boiling. Mature, filter and ignite the barium sulfate precipitate as specified in 10.1.5. Weigh to the nearest 0,1 mg and calculate the mass of precipitate (m7).

12.5 Calculation and expression of results Calculate the acid soluble sulfate content of the aggregate, expressed as SO3 to the nearest 0,1%, from the following formula: Sulfate content (SO3) = m7/m6 × 34,30 (in %)

38

(12)

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where m7

is the mass of precipitate in grams;

m6

is the mass of the test portion in grams.

NOTE 1 Results can be expressed in SO4 using the following formula:

Sulfate content(SO4) = m7/m6 × 41,16 (in %) NOTE 2 A statement on the precision of the determination of the acid soluble sulfate content is given in Annex A."

13

Determination of acid soluble sulfides

13.1

Principle

The test portion is decomposed by hydrochloric acid under reducing conditions. The sulfides are converted into hydrogen sulfide, which is carried over by a gaseous stream into an ammoniacal solution of zinc sulfate. The precipitated zinc sulfide is determined by iodometry.

13.2

Sampling


13.3

the laboratory sample should be representative of the moisture content of the batch.


Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 (7.3) appropriate to the upper (D) sieve size of the aggregate. If necessary, dry the sample at a temperature of (110 ± 5) °C. NOTE


Stepwise crush and reduce the sub-sample to a mass of approximately 20 g and then grind the particles until they all pass the 125 µm sieve. Take approximately 1 g of this material as the test specimen.

13.4

Procedure

Use the apparatus shown in 5.8 and Figure 1. Weigh the test portion to the nearest 0,1 mg (m8) and transfer into a 250 ml stoppered round bottom flask with a ground glass joint. NOTE 1 If the sulfide content is low (< 0,1 %), reagent solutions ten times more dilute should be used (4.7.5 and 4.7.6).

Add about 2,5 g of tin (II) chloride (4.7.3) and 0,1 g of chromium (4.7.4). NOTE 2

Chromium contributes to the dissolution of any pyrites (FeS2) that may be present in the aggregate.

Disperse the mixture in 50 ml of demineralized water. Fix to the flask the ground neck supporting the separating funnel and connect this neck to the inlet of the condenser; connect the outlet of the condenser to the glass tube which dips into the beaker containing 15 ml of ammoniacal zinc sulfate solution (4.7.2) and 285 ml of demineralized water.

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Connect the gas supply (nitrogen or argon) and adjust the flow to about 10 ml per min. Stop the flow of gas. Release 50 ml of hydrochloric acid (1 + 1) (4.1) from the separating funnel taking care that a small amount of acid remains in the separating funnel to prevent leakage. Reconnect the gas supply, heat the contents of the flask to boiling and boil for 10 min. Disconnect the outlet tube, which will serve as a stirrer during the titration. Aggregates of higher sulfide content will require more than 10 min reaction time for complete transformation of all sulfides to precipitated zinc sulfide. Check that the extraction is complete by bubbling the outlet into fresh ammoniacal zinc sulfate solution. If no precipitate appears, the extraction is complete. Cool the receiver to 20 °C and add by pipette 10 ml of the 0,016 6 mol/l potassium iodate solution (4.7.5) and 25 ml concentrated hydrochloric acid (4.1). Titrate with sodium thiosulfate solution (4.7.6) until pale yellow. Then add 2 ml of starch solution (4.7.7) and titrate until the colour changes from blue to colourless.

13.5


Calculate the sulfide content of the aggregate, expressed in S, from the following equation:

S=

{(V9 × F ) − (V10 × f )}×1,603 ×100 = 0,160 3 × {(V9 × F ) − (V10 × f )}(in %) 1 000 × ms

ms

(13)

where V9

is the volume of the potassium iodate solution in ml;

F

is the factor of the potassium iodate solution as specified in 4.7.5;

V10

is the volume of sodium thiosulfate solution used for the titration in ml;

f

is the factor of the sodium thiosulfate solution as specified in 4.7.6;

m8

is the mass of the test portion in g.

14 14.1 14.1.1

Determination of components affecting the surface finish of concrete Examination for the presence of reactive iron sulfide particles General

This clause specifies methods for detection of iron sulfide particles which, when present at or near the surface of concrete, can cause the formation of brown stains that are very difficult to remove. 14.1.2

Sampling

The stockpile shall be inspected and approximately 50 particles, representative of those suspected to contain iron sulfide, shall be taken for testing.

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14.1.3

Procedure


Determine the reactivity of the particles by placing them in a saturated limewater solution. NOTE 1 A blue-green gelatinous precipitate of ferrous sulfate should form within 5 min. This precipitate changes rapidly to brown ferric hydroxide on exposure to air and light. This reaction should be complete within 30 min and indicates the presence of rapidly reacting iron sulfide.

If no brown gelatinous precipitate is formed when the particles are placed in saturated limewater, they may be slowly reacting particles. When presence of slowly reacting particles is suspected, examine the particles visually to assess as well as possible their propensity to cause staining in mortar or concrete. NOTE 2 Where a particular quarry has a history of occasionally producing aggregate containing iron sulfide, examination with a low power microscope by a technologist with experience of the quarry may be sufficient to determine whether or not the material is deleterious.

In other cases, embed the recovered particles in Portland cement paste, store for 28 days in a moist condition and then examine the cement paste for staining.

14.2 14.2.1

Determination of lightweight contaminators General

This test is a method for estimating the mass percentage of lightweight particles in fine aggregate. The method estimates substances such as lignite and coal which may cause staining or pop-outs on concrete or mortar surfaces. If necessary, the method can be adapted for use on coarse aggregates by examining larger test portions (see Table 1). 14.2.2

Principle

Most normal weight fine aggregates for concrete and mortar have a particle density greater than 2,0. When a test portion of the fine aggregate is immersed in a liquid with a density just below 2,0, lower density particles will float on the surface. This allows them to be removed for examination and quantification. NOTE

14.2.3

The flotation process cannot be used with lightweight aggregates.

Procedure

The minimum quantity of fine aggregate in the laboratory sample shall be 5 kg. This shall be reduced to produce a test portion of mass (350 ± 50) g. Spread the test portion over a tray and dry it to constant mass (6.4) at (110 ± 5) °C. Record the mass of the dried test portion (m9) to the nearest 0,1 g. Separate the aggregate on the 300 µm sieve (5.9.1), discarding the finer fraction. Pour about 1 l of the solution of zinc chloride (4.8.1) or sodium polytungstate (4.8.2) into a 2 l beaker and then pour the aggregate into the solution. Gently agitate the bed of aggregate with a glass rod to assist lightweight particles to leave the bed and rise to the surface of the solution. Gently agitate the floating particles with the glass rod to dislodge any air bubbles that may have caused heavier aggregate particles to float. Decant the supernatant solution into a second 2 l beaker through a 250 µm sieve (5.9.1), allowing the floating particles to be retained on the sieve. Ensure that none of the heavier aggregate particles pass into the sieve. Return the solution to the first beaker and agitate the bed of aggregate again. If further particles float on the solution, decant through the sieve again. Repeat the procedure until all of the floating particles have been collected in the sieve.

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Wash the sieve and the particles on it with water until the zinc chloride or sodium polytungstate has been removed. Dry the sieve and contents for (20 ± 4) h at (40 ± 5) °C and then tip the contents into an evaporating basin (5.9.2). Complete the drying at (110 ± 5) °C for (4 ± 0,25) h. Cool the basin and then weigh the lightweight particles (m10), to the nearest 0,1 g. 14.2.4


Calculate the percentage of lightweight particles in the aggregate, expressed as mLPC, from the following equation: mLPC = (m10/m9)) 100

(in %)

(14)

where m9

is the mass of the oven dried test portion in g;

m10

is the mass of oven dried lightweight particles separated from the test portion in g.

The result shall be recorded to the nearest 0,1 %.

15 Determination of organic components affecting the setting and the hardening of cement 15.1 15.1.1

Determination of potential presence of humus Principle

Humus is an organic substance which forms in the ground by the decomposition of animal and plant residues. The humus content of aggregate is estimated from the colour formed when a test portion is shaken in a sodium hydroxide solution. NOTE The method is based on the principle that humus develops a dark colour when it reacts sodium hydroxide (NaOH). The intensity of the colour depends on the humus content. If the solution is clear or only slightly coloured, the aggregate does not contain an amount of humus that is considered to be significant. A strong colour reaction will usually reflect high humus content, but can be due to other factors. In this case, the method does not give a definitive conclusion.

15.1.2

Sampling


15.1.3



Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 (7.3) appropriate to the upper (D) sieve size of the aggregate. Dry the sub-sample in a drying oven (5.2.1) at (40 ± 5) °C (6.4). Sieve the dried particles on a 4 mm sieve (5.10.1) and retain the fraction that passes.

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15.1.4

Procedure

Pour a 3 % sodium hydroxide (NaOH) solution (4.9.1) into the glass bottle (5.10.2) to a height of about 80 mm. Then pour some of the test portion into the glass bottle until the height of aggregate and solution is 120 mm. Shake the bottle to enable air bubbles to escape. Stopper the bottle and shake it vigorously for 1 min. Leave it to stand for 24 h. Compare the colour of the solution to the standard colour solution (4.9.2), contained in a similar clear cylindrical glass bottle. Record whether the colour of the solution is lighter or darker than the standard colour. 15.1.5

Expression of results

The test result shall state whether the colour of the solution is Negative Test (lighter than the standard colour) or Positive Test (darker than the standard colour) (4.9.2).

15.2 15.2.1

Determination of fulvo acid content Principle

This clause specifies a method for the determination of the fulvo acid content of fine aggregates. Fulvo acids are components of the humic acids which have a retarding effect on the hydration of cements. Fulvo acids dissolve in hydrochloric acid producing a yellow colour. The intensity of the colour increases as the concentration of fulvo acids increases. Compounds of Fe(III) produce a brown colour in hydrochloric acid. This colour is eliminated by converting Fe(III) compounds to colourless Fe(II) compounds using stannous chloride solution. 15.2.2

Sampling


15.2.3



Reduce the laboratory sample to a test portion of (100 ± 0,5) g, using the procedures specified in EN 932-2. The moisture content of the test portion shall not be greater than 10 % by mass of the sample. Test portions with moisture contents greater than 10 % shall be dried at a temperature of (40 ± 5) °C until the moisture content is reduced to 10 % or less. 15.2.4

Procedure

Carry out the test at a room temperature of (20 ± 2) °C. Weight the test portion into a 250 ml or 300 ml flask (5.2.9). Add 100 ml of hydrochloric acid (1 + 23) (4.1 and 4.10.1). Allow the flask and its contents to stand for 4 h, shaking it occasionally. Filter 75 ml of the solution from the flask into a clear glass 250 ml graduated cylinder (5.2.11). Use a 10 ml graduated cylinder (5.2.11) to add 10 ml of clear stannous chloride solution (4.10.2). If after adding the stannous chloride the solution becomes turbid, sulfides are present. If this happens, repeat the test by boiling the solution for 5 min on a hot plate (5.11.4) before adding the stannous chloride.

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Let the 250 ml graduated cylinder and its contents stand for a further 1 h then fill to the 100 ml graduation mark with hydrochloric acid (1 + 23) (4.10.1). Mix the contents of the cylinder using a glass stirring rod (5.11.1). Compare the colour of the resulting solution to the standard colour solution (4.9.2), contained in a similar clear glass graduated cylinder (5.2.11). Record whether the colour of the solution is lighter or darker than the standard colour. 15.2.5


The test result shall state whether the colour of the solution is Negative Test (lighter than the standard colour) or Positive Test (darker than the standard colour) (4.9.2).

15.3 15.3.1

Determination of organic contaminators by mortar method Principle

The mortar method is a performance test intended to demonstrate and quantify any effects which organic contaminators in aggregate can have on the stiffening and hardening of mortar. The principle of the method is to prepare two nominally identical mortars and test them for stiffening rate and compressive strength. One mortar contains the test aggregate as received while the other mix is prepared from a duplicate test portion which has been heated to destroy organic matter. The heated aggregate acts as a control alongside which the original aggregate is compared. The stiffening test assesses acceleration or retardation of the setting of the mortar, while the 28-day strength indicates any longer term effect. 15.3.2

Sampling

The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. The laboratory sample shall have a mass of at least 15 kg. 15.3.3

Preparation of test portions

Dry the laboratory sample by spreading it onto trays and allowing it to dry naturally in the laboratory at ambient temperature. Using the procedures specified in EN 932-2, further reduce the dried laboratory sample to produce four test portions each of (1 900 ± 100) g. When reducing the dried laboratory sample to produce test portions for the mortar method, should a splitting operation produce two test portions each of mass less than 1,8 kg, then one test portion shall be split once, or twice, or if necessary three times to yield a sub-sample which when added to the first produces a combined mass of no more than 2 kg. NOTE

15.3.4

For lightweight aggregate, the volume of each test portion shall be 1 l.

Preliminary treatment of test portions

15.3.4.1 Retain of the two test portions (15.3.3) in sealed containers, without further treatment. Heat the other two test specimens using the procedure in 15.3.4.2. 15.3.4.2 Pour a test portion into a weighed porcelain or silica basin (5.12.2), weigh and place in the muffle furnace (5.12.7) at ambient temperature. NOTE If only a small furnace is available, each test portion can be divided into two or more parts. The parts should be weighed, heated and reweighed separately; and recombined when cool.

Raise the temperature of the furnace to (480 ± 25) °C over a period of (4 ± 0,25) h.

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Maintain the temperature of (480 ± 25) °C for (4 ± 0,25) h and then allow the furnace to cool down to ambient temperature (usually overnight). Weigh the basin and aggregate and record the loss in mass.


Repeat this procedure with the second test portion. 15.3.5

Constituents

The cement shall be stored in an airtight container. 15.3.6 15.3.6.1

Mix quantities General requirements and trial mixes

Each mortar mix shall contain either a test portion of the unheated aggregate, or a test portion of the aggregate previously heated as in 15.3.4. Each mortar mix shall also contain CEM I cement of mass one quarter that of the aggregate mass in the mix. The test portions and the cement shall be weighed to ± 1 g. The water content of the mortars containing the unheated aggregate shall be chosen to produce a standard consistence, defined as a mean plunger (5.12.3) penetration of (23 ± 0,5) mm, when determined using by the plunger test method given in EN 1015-4. For lightweight aggregate, use 300 g of cement for each mortar mix and 30 g for each preliminary test. To establish the required water contents, prepare a series of trial mixes using the unheated aggregate. Vary the water content successively and measure the consistence of each trial mix until the correct value of consistence is attained. Note the mass of water contained in this last mix and calculate the water-cement ratio. Reject the trial mixes. NOTE 1 The unheated test aggregate should have similar moisture content to the heated (control) aggregate when it was weighed before heating. This means that the trial mixes and mortar test specimens made with the test aggregate should be prepared on the same day as the heating procedure (15.4.3) is started for the control aggregate. NOTE 2 Control mixes will usually be prepared a day after the test mixes. Laboratory conditions should be as similar as practicable on the two mixing days.

15.3.6.2

Test mixes

Calculated the required mass of cement for each unheated test portion (15.3.6.1). Using the water-cement ratio obtained using the trial mixes in 15.3.6.1, calculate the mass of water required for each mix and weigh to ± 0,5 g. 15.3.6.3

Control mixes

Ensure that the water-cement ratio of the heated aggregate control mortars is the same as that of unheated aggregate test mortars by first calculating the required mass of cement and water for each mix as in 15.3.6.2. Then add to each calculated mass of water, the mass lost by the corresponding portion of aggregate during the heating detailed in 15.3.4.2. Weigh the required mass of water to ± 0,5 g. 15.3.7

Mixing procedure

15.3.7.1 Four mixes are required; one for each test portion. Bring all the materials to a temperature of (20 ± 2) °C before starting the mixing procedure and mix in a room or other controlled environment with a temperature of (20 ± 2) °C and a relative humidity of not less than 50 %. Prepare each mix using the procedure in 15.3.7.2.

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15.3.7.2 Place the test portion and then the cement in the dry mixing bowl (5.12.4) and mix for 30 s. Continue mixing and add the water during the next 30 s. Continue mixing for a further 60 s after all the water has been added. Stop the mixer and clean any adhering material from the paddle and sides into the bowl using a scraper, taking particular care to ensure that no unmixed materials remain at the bottom of the bowl. Complete this part of the procedure within 60 s. Cover the bowl with a damp cloth and allow to stand for 5 min. Replace the bowl in the mixer and mix the mortar for a further 60 s. 15.3.8

Measurement of stiffening time

Immediately after completion of mixing of each mortar, determine the stiffening rate in accordance with EN 1015-9. Record the stiffening times of the duplicate test portions of unheated and heated (control) aggregates. 15.3.9

Compressive strength of hardened mortar

Prepare three 160 mm × 40 mm × 40 mm prisms from each mortar mix, using the procedure specified in EN 1015-11. Determine the density of each prism on demoulding. Test the prisms for compressive strength after 28-days in accordance with EN 1015-11. Record the 12 compressive strengths for the duplicate test portions of unheated and heated (control) aggregates. 15.3.10


15.3.10.1 Stiffening time Calculate the change in stiffening time by subtracting the mean stiffening time of the heated aggregate mortars from the mean stiffening time of the unheated aggregate mortars. Express the result to the nearest 15 min. NOTE

A negative result indicates that organic contaminators accelerated the setting of the mortar.

15.3.10.2 Compressive strength Calculate to the nearest 1 % the relative compressive strength S % of the unheated aggregate mortar by the following equation: S = (A/B) 100 ( in %)

(15)

where A

is the mean compressive strength of the six unheated aggregate prisms, in N/mm²;

B

is the mean compressive strength of the six heated (control) aggregate prisms, in N/mm².

NOTE Organic contaminators can entrain air in mortar mixes. Entrained air can also affect compressive strength. The presence of entrained air can be assessed by comparing the mean mass and density of the two sets of prisms.

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16

Determination of water solubility


16.1 16.1.1

Determination of water solubility of aggregate, excluding filler Principle

The aggregate test portion is extracted with twice its own mass of water in accordance with the procedure specified in 10.1.4. After extraction, the recovered aggregate is dried and weighed. NOTE

16.1.2

The water solubility of filler is determined using the procedures in 16.2.

Sampling


16.1.3



Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 (7.3) appropriate to the upper (D) sieve size of the aggregate. Dry the sample at a temperature of (110 ± 5) °C. Weigh the dried test portion to the nearest 0,1 g (m11). 16.1.4

Extraction of soluble components

Extract the soluble components from the aggregate using the procedure specified in 10.1.4 and then allow most of the solids to settle. Filter as much of the supernatant liquid as is practical on a pre-weighed medium-grade filter paper (5.3.4). Transfer the settled aggregate from the extraction bottle, with the aid of a minimum amount of water, to a pre-weighed porcelain evaporating basin (5.9.2). Add the filter paper and the retained particles to the aggregate in the basin. Dry and then cool the contents of the basin to constant mass (3.4 and 6.4) and weigh to the nearest 0,1 g. Calculate the mass of dried aggregate by subtracting the masses of the basin and the mass of the filter paper (m12). 16.1.5


Calculate the water solubility of the aggregate, expressed as WS, from the following equation:

WS =

m11 − m12 × 100 (in %) m11

(16)

where m11

is the mass of aggregate before extraction in g;

m12

is the mass of aggregate after extraction in g.

Record the result to 0,1 %.

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16.2

Determination of water solubility of filler


16.2.1

Principle

The filler test portion is extracted with fifty times its own mass of water. After extraction, the recovered filler is dried and weighed. 16.2.2

Sampling


16.2.3



Reduce the laboratory sample by the procedures specified in EN 932-2, to an amount not less than 25 g. Dry the sub sample at a temperature of (110 ± 5) °C to constant mass (6.4). Take two test specimens, each of (5 ± 0,2) g. 16.2.4

Extraction of soluble component

If the filler contains added calcium hydroxide, determine the calcium hydroxide content (Ka) according to EN 459-2. Weigh two 500 ml Erlenmeyer flasks (5.3.2) to the nearest 0,01 g. Transfer the test specimens to the flasks, weigh the two flasks and contents and record their mass to the nearest 0,01 g. Calculate the mass of filler in each flask by difference (m11). To each flask, add a mass of water equal fifty times the mass of the test specimen. Stopper the flasks and mix the contents by shaking (5.3.3) continuously with sufficient agitation to avoid any sedimentation for a minimum of 24 h. Filter as much of the supernatant liquid as is practical on a pre-weighed filter funnels fitted with mediumgrade filter paper (5.3.4), leaving the remaining residue in the Erlenmeyer flasks. Dry and then cool the Erlenmeyer flasks, filter funnels, filter papers, and their contents to constant mass (3.4 and 6.4) and weigh to the nearest 0,1 g. Calculate the mass of dried filler by subtracting the masses of the basin and the mass of the flasks, funnels and filter papers (m12). 16.2.5 Calculation and expression of results Calculate the water solubility of the filler or the mixed filler, expressed as WS, from the following equation:

WS =

m11 − m12 × 100 − K a (in %) m11

where m11

is the mass of filler before extraction in g;

m12

is the mass of filler after extraction in g;

Ka

is the determined calcium hydroxide content of a mixed filler, with a maximum of 8,4 %.

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(17)

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Record the result to 0,1 %.


NOTE 1 Mixed filler contains added calcium hydroxide. If the calcium hydroxide value is less than 8,4 % the determined value is used. For other mixed fillers a value of 8,4 % is used. NOTE 2

17

For fillers that do not contain added calcium hydroxide, Ka = 0.

Determination of loss on ignition

!

17.1 Principle The loss on ignition is determined in an oxidizing atmosphere. By igniting the aggregate in air at (950 ± 25) °C the carbon dioxide and the water not evaporated during drying are driven off, as are any oxidizable volatile elements present. NOTE 1 If the aggregate contains non-volatile oxidizable constituents, as in the case of blast-furnace slags, the loss on ignition should be corrected in accordance with EN 196-2:2005, 7.4. NOTE 2 For aggregates produced from incinerator residues, the ignition temperature should be (480 ± 25) °C. NOTE 3 This test may be used as an alternative test for humus content. In that case temperature should be (480 ± 25) °C.

17.2 Sampling and preparation of test portion The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. The laboratory sample should be representative of the moisture content of the batch. Reduce the laboratory sample by the procedures specified in EN 932-2 to an amount not less than the mass specified in Table 1 (7.3) appropriate to the upper (D) sieve size of the aggregate. If necessary, dry the sample at a temperature of (110 ± 5) °C. NOTE


Stepwise crush and reduce the sub-sample to a mass of approximately 20 g and then grind the particles until they all pass the 125 µm sieve. Take (1 ± 0,05) g of this material as the test specimen.

17.3 Procedure for the determination of loss on ignition Weigh the test portion to the nearest 0,1 mg (m13) into a crucible (5.6.2) which has been previously ignited and tarred. Place the crucible in the electric furnace (5.2.2) controlled at (950 ± 25) °C. Leave the crucible in the furnace for at least 60 min. Cool the crucible to room temperature in a desiccator (5.2.16) and then re-weigh (m14). In the case of calcareous aggregates, heating to 950 °C should proceed slowly to minimize the risk of violent decrepitation.

17.4 Calculation and expression of results Calculate the loss on ignition of the aggregate from the following formula:

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Loss on ignition =

m13 − m14 × 100 (in %) m13

(18)

where m13 m14

is the mass of the initial test portion in grams; is the mass of ignited test portion in grams.

The temperature of ignition used shall be reported."

18 18.1

Determination of free lime in steel slag General

Each of the methods specified in this clause determine the presence of free lime (CaO), which is potentially expansive, and hydrated lime (Ca(OH)2) which is not expansive. To distinguish between these two forms of lime, extra tests are necessary, such as thermo gravimetric or X-ray diffraction analysis.

18.2 18.2.1

Determination of free lime by complexometry (Reference method) Principle

Free lime is extracted from a ground sample of aggregate by hot ethanediol. The content of calcium ions in the extract is subsequently determined by complexometric titration. 18.2.2

Sampling and preparation of test portion

Proceed as specified in 11.1.2 and 11.2.3 but crushing the last 20 g until they all pass a 63 µm sieve and take approximately 0,5 g of this material as the test portion. Coarse iron fragments remaining on the sieve shall be removed. 18.2.3

Procedure

Weigh the test portion to the nearest 0,1 mg (m15) and transfer into the conical flask (5.13.1) already containing a PTFE stirrer. Measure 50 ml of anhydrous ethanediol (4.11.1) and transfer into the flask. Seal the flask with the glass stopper and stir in a 70 °C water bath for 30 min after reaching the temperature, using the magnetic stirrer at 300 rpm to 400 rpm. Then filter immediately through the sintered glass filter (5.13.4), which has a layer (approximately 4 mm to 5 mm) of firmly rammed filter paper pulp in ethanediol. Wash out the flask three times with a total of 50 ml propan-2-ol (4.11.2). Acidify the clear filtrate, containing the dissolved free lime, with 10 ml of hydrochloric acid (1 + 1) (4.11.4) and rinse through with water into the measuring flask (5.13.2). Fill up to the mark and homogenize by shaking. In accordance with the presumed content, transfer 50 ml or 100 ml to a glass beaker using a pipette. Add ten drops of m-nitrophenol solution (4.11.6) and ten drops of triethanolamine (4.11.5) (to sequester the Mn and Fe ions), and then neutralize with the 2 mol/l NaOH solution (4.11.7); dilute with water to approximately 500 ml and bring the pH-value to greater than 13 by adding about 10 ml of 2 mol/l NaOH solution. Add indicator (4.11.8) and titrate with EDTA solution (4.11.9) until the reddish mauve changes to blueish mauve. Determine the end point of titration by using the photoelectric titration equipment (5.13.5). A blank value shall always be determined from the ethanediol and the reagents.

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18.2.4



Calculate the free lime content of the aggregate from the following equation:

Free Lime =

(V11 − V12 )× F ×100 (in % ) m15

(19)

where V11

is the volume of EDTA solution added (in ml);

V12

is the volume of EDTA solution added for the blank (in ml);

F

is the EDTA solution factor in mg of CaO per ml; multiply by 0,5 in the case of pipetting 100 ml out of the flask (5.13.2);

m15

is the mass of the test portion (in g).

The amount of free lime is rounded to the nearest 0,1 %.

18.3 18.3.1

Determination of free lime by conductometry (Alternative method) Principle

Free lime is extracted from a ground sample of aggregate by hot ethanediol. The content of calcium ions in the extract is subsequently determined by conductance measurements. 18.3.2


Proceed as specified in 18.2.2 and take (100 ± 0,1) mg of the passing 63 µm material as the test portion. 18.3.3

Procedure

Preheat 100 ml of ethanediol (4.11.1) to (80 ± 0,1) °C in the measuring vessel (see Figure 2) with the aid of a connected thermostat, stirring with a magnetic stirrer. Add the test portion to this solvent and introduce the measuring electrode. NOTE By measuring the conductance during extraction time, the dissolution of the free lime can be monitored directly.

After an extraction time of at least 10 min and when no further change in conductance occurs, the extraction process is completed. Then read off the final conductance value. 18.3.4

Evaluation and expression of results

Convert the measured conductivity into free lime content using a calibration graph (see Figure 3). Express the mass percentage of free lime to the nearest 0,1 %.

18.4 18.4.1

Determination of free lime by acidimetry (Alternative method) Principle

Free lime is extracted from a ground sample of aggregate by boiling in ethyl acetoacetate (Franke method); the extract is titrated with a standard 0,2 mol/l hydrochloric acid solution.

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18.4.2



Proceed as specified in 18.2.2 and take approximately 1 g of the passing 63 µm material as the test portion. 18.4.3

Procedure

Measure 70 ml of the prepared solvent solution (4.13.5) containing ethyl acetoacetate and 2methylpropan-1-ol in the proportion of 3 to 20, and transfer into the Erlenmeyer flask (5.15.1). Weigh the test portion to the nearest 0,1 mg (m16) and transfer into the flask. Adjust the flask in position to the water-cooled condenser, fitted with the upper adapter tube containing the sodium hydroxide (4.13.8) and the molecular sieve (5.15.3); reflux at boiling temperature, stirring on the hot plate (5.2.7) for 3 h. Remove the hot plate, allow to cool, then filter under vacuum through the glass microfibre filter (5.15.4), receiving the filtrate in a second flask. Wash the first flask and residue with 50 ml of 2-methylpropan-l-ol (4.13.2), using a stirring rod fitted with a rubber policeman to guide the flow. Add 10 to 12 drops of the indicator solution (4.13.6) to the filtrate and titrate with the standard 0,2 mol/l hydrochloric acid solution (4.13.7) to a distinct reddish tinge. NOTE If the titration is conducted by means of a recording pH meter, the filtration of the extract is not necessary.

18.4.4


Calculate the free lime content of the aggregate from the following equation: Free lime = k/1 000 V12/m16 100 (in %)

(20)

where V12

is the volume of hydrochloric acid added (in ml);

m16

is the mass of the test portion (in g);

k

is the factor defined in 4.13.7, representing the number of mg of free CaO per ml of standardized hydrochloric acid solution.

18.5

Determination of CaO in steel slag by X-ray diffraction

18.5.1

Principle

In wet chemical analyses “free lime” is determined by selective extraction of the minerals CaO (free lime, in its narrower sense as detrimental slag constituent) and Ca(OH)2 (Portlandite, the hydration 2+ product of CaO). The concentration of Ca ions is analysed and expressed as CaO, i.e. “free lime”. By X-ray diffraction both minerals (free lime = CaO and Portlandite = Ca(OH)2) can be distinguished due to their different crystal structure. The intensities of the measuring signals are proportional to the concentrations of CaO and Ca(OH)2. NOTE The crystal structure of each mineral is a three-dimensional, periodic framework of atoms. This framework can be described by different sets of parallel lattice planes. Each single set of parallel lattice planes has a constant spacing “d”. X-ray diffraction can be understood as reflection of X-rays by the different sets of lattice planes.

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Any X-ray diffraction device records a signal – called "peak" in the following text – if Bragg’s law is fulfilled:


n λ = 2 d sin θ where n λ θ d

= whole number; = wave length of the used X-radiation; = diffraction angle of the reflected X-radiation; = lattice spacing.

Each mineral is characterized by a set of specific d-values and corresponding intensity ratios. These sets are listed in literature, i.e. commercially available data files. Please note that in X-ray diffraction °θ or °2 θ is frequently used as read-out of the instrument. θ or 2 θ is linked to the d-values of a mineral by Bragg’s law and depends on the wavelength of the used Xrays. 18.5.2 18.5.2.1

Procedure of analysis Starting and stopping the X-ray powder diffraction device

Follow up the procedure in the instruction manual of the X-ray powder diffraction device used. 18.5.2.2

Preparing the sample

Sample preparation shall be done within short time to prevent further hydration of CaO by humidity. Contact with water shall be avoided. The laboratory sample taken shall be dried immediately in the laboratory at (110 ± 5) °C until a constant mass (3.4) is reached. A sub-sample of at least 30 g shall be crushed until all of it passes a sieve with 63 µm woven wire cloth complying with the requirements of EN 933-2. Then this sub-sample shall be prepared in accordance with the requirements of the X-ray device. 18.5.2.3

Analysis

Before any operation, make sure that the equipment is in an optimal operational condition (refer to the manual of the X-ray diffraction device). To perform an analysis of free lime (CaO) and Portlandite (Ca(OH)2) in steel slag strong intensities of these minerals shall be used, preferably the intensities at dCpeak = 2,389 Å for free lime (CaO) and dCHpeak = 4,895 Å for Portlandite (Ca(OH)2). X-ray intensities of steel slag minerals usually are broadened peaks, due to imperfect crystals and/or partial substitution of Ca by other elements. For this reason a d-range around the above mentioned intensities shall be scanned. Make sure that there is no serious interference with other minerals of the slag or of impurities in the steel slag.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

Make a background correction for free lime (CaO) and Portlandite (Ca(OH)2), preferably at:


dCb1 = 2,427 Å and dCb2 = 2,335 Å for free lime (CaO) and dCHb1 = 4,950 Å and dCHb2 = 4,860 Å for Portlandite (Ca(OH)2). Select measuring times for each background left and right of the peaks and the d-ranges that ensure statistic save analytical results. Standard deviation in impulse statistics follows square root (N), with N = counts (number of detected impulses). Make sure that calibration measurements and analyses are performed under identical operational conditions and same d-values for intensities and background. Make a correction for loss of intensity of the X-ray tube. EXAMPLE 1

An example of a measuring procedure for free lime (CaO) is as follows:

Measure the background intensity ICb1 at dCb1 = 2,427 Å for 160 sec. Scan the range dCb1 = 2,427 Å to dCb2 = 2,335 Å in steps of 0,01 °2 θ/sec and report the intensity ICRange. Measure the background intensity ICb2 at dCb2 = 2,335 Å for 160 sec. ICRange shall be at least 3 x square root ((ICb1 + ICb2)/2). Calculate IC = ICRange – (ICb1+ICb2)/2. Use IC for all further calculations. EXAMPLE 2

An example of a measuring procedure for Portlandite (Ca(OH)2) is as follows:

Measure the intensity ICHb1 at dCHb1 = 4,950 Å for 160 sec. Scan the range dCHb1 = 4,950 Å to dCHb2 = 4,860 Å in steps of 0.01 °2 θ/sec and report the intensity ICHRange. Measure the intensity ICH2 at dCH2 = 4,860 Å for 160 sec. ICHRange shall be at least 3 x square root ((ICH1 or ICH2)/2). Calculate ICH = ICHRange – (ICH1+ICH2)/2. Use ICH for all further calculations.

18.5.3 Calibration procedure 18.5.3.1

General

A calibration curve shall be established that links the intensity of the diffracted ray with the free lime contents on of reference samples with known concentrations based on one of the following methods. 18.5.3.2

Establishing a calibration curve for free lime in steel slag

Take reference samples in the converter, by means of a spoon. NOTE Considering the temperature of the slag at the moment of the sampling (1 600 °C to 1 700 °C) it can be assumed that hydrated lime (Portlandite) is totally absent.

After crushing, these samples are analysed in accordance with 18.2 to determine the contents of free lime. The diffracted intensity by free lime (CaO) is measured for each of the samples in accordance with 18.5.2.3 and the calibration curve for the CaO is then established. 18.5.3.3

Establishing a calibration curve for Portlandite in steel slag

The reference samples used for establishing the calibration curve of free lime (CaO) are hydrated during 48 h in a beaker with excess water. After drying, the absence of free lime is confirmed by comparison between the analysis of the hydrated samples and the calibration curve of free lime.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

The intensity diffracted by Portlandite (Ca(OH) 2) is measured in accordance with 18.5.2.3 and the calibration curve for (Ca(OH) 2) is then established.


18.5.3.4

Establishing a calibration curve for free lime and Portlandite in steel slag

Prepare synthetic mixtures of the relevant steel slag and reagent-grade CaO or Ca(OH)2. The intensity diffracted by free lime (CaO) or Portlandite (Ca(OH)2) is measured in accordance with 18.5.2.3 and the calibration curves for free lime (CaO or (Ca(OH) 2) is then established. 18.5.4

Analytical results

Report the results to an accuracy of 1 %.

19 19.1 slag 19.1.1

Determination of unsoundness of blast-furnace and steel slags Determination of dicalcium silicate disintegration of air-cooled blast-furnace

General

This clause specifies the method of determination of the susceptibility to disintegration of crushed blastfurnace lump slag resulting from the inversion of the metastable ß form of the dicalcium silicate to the γ form. This phenomenon is sometimes improperly called "lime disintegration". 19.1.2

Principle

Broken slag surfaces fluoresce under ultra-violet light in the range of visible light. The aspect and colour of fluorescence enable the detection of slags liable to silicate disintegration. 19.1.3

Sampling

Proceed as specified in 11.1.2. 19.1.4


Reduce the laboratory sample to a test portion of at least 30 lumps, then wash and dry the test portion, then split each lump to obtain freshly broken surfaces. 19.1.5

Procedure

Carry out the dicalcium silicate disintegration test under ultra-violet light (5.17.1). 19.1.6


Record the observations made on the appearance of freshly broken surfaces. Slags which exhibit numerous or clustered large and small bright spots of a yellow, bronze or a cinnamon colour on a violet background shall be recorded as suspect with respect to disintegration. Slags with a uniform shine in various shades of violet and those exhibiting bright spots in a limited number only and uniformly distributed, shall be deemed sound.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

19.2


19.2.1

Determination of iron disintegration of air-cooled blast-furnace slag General

This clause specifies the method of determination of the susceptibility to disintegration of crushed blastfurnace slag, resulting from the hydrolysis of iron- and manganese sulfides. 19.2.2

Principle

The iron disintegration occurring by ageing in a humid atmosphere or in rain, but more rapidly under water, is observed by examining the behaviour of pieces of slag which have been immersed in water. 19.2.3

Sampling

Proceed as specified in 11.1.2. 19.2.4

Procedure

Place 30 pieces of slag, with a nominal size between 40 mm and 150 mm, in water at (20 ± 2) °C for two days. 19.2.5


Record any cracking or disintegration. If no pieces disintegrate or crack, the sample shall be regarded as having passed the test. If one or two pieces disintegrate or crack, the test shall be repeated with a further 30 test pieces. If any pieces disintegrate or crack in the second test the sample shall be regarded as having failed the test.

19.3 19.3.1

Determination of the expansion of steel slag General

This clause specifies the method of determination of the susceptibility to expansion of crushed steel slag, resulting from the late hydration of dead burned free lime and/or free magnesium oxide. The test is accelerated due to the elevated temperature and is designed to generate measurable values of expansion for the purpose of categorizing suitable slag. 19.3.2

Principle

A compacted slag specimen, combined from known grain sizes, is subjected to a flow of steam at 100 °C in a steam unit at ambient pressure. By this means, the necessary moisture for reaction with the free lime and free magnesium oxide is continuously conveyed to the test specimen. Any change in the volume caused by this reaction is read off from a displacement indicator directly at the top of the specimen. The increase in volume is given as the result, calculated in % volume in relation to the original volume of the compressed slag specimen. The values are not directly indicative of those expected in the field, i.e. 4 % expansion in the test does not equate to 4 % uniform expansion in the field. 19.3.3

Sampling

The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. 19.3.4

Preparation and compaction of the specimens

The laboratory sample taken shall be dried immediately in the laboratory at (110 ± 5) °C until a constant mass (3.4) is reached.

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


For the steam test use 0 mm to 22 mm test portions of dried mineral mixtures of slag, which have been combined in accordance with the Fuller parabola. The proportions of mass for the individual grain size classes are given in Table 2. Table 2 — Proportions of mass per grain size class Sizes

Percentage

mm

in mass

0 to 0,5

15

0,5 to 2

15

2 to 5,6

20

5,6 to 8

10

8 to 11,2

11

11,2 to 16

14

16 to 22

15

Total

100

NOTE 1 if there are great differences in the particle densities of the individual grain size classes, the mineral mixture can be combined using proportion of volume.

The individual grain size classes shall be taken from the crushed aggregates. The sample reduction shall be carried out in accordance with the procedures specified in EN 932-2. The expansion shall be determined on at least two test specimens. Each individual test portion shall be combined separately with the above-mentioned size distribution. The amount of material required for each individual sample is 4,5 kg. In addition, a sample shall be combined for the determination of the pre-dried particle density, in accordance with EN 1097-6. Cover the perforated base of the test cylinder with a circular filter (fabric mat) and, using a laboratory scoop, transfer the prepared test portion to the cylinder (5.18.1) illustrated in Figure 5. Then dynamically compact the dry specimen on the vibrating table (5.18.5) for 6 min at a frequency of (48 ± 3) Hz (amplitude ± 1,5 mm) and a static load of 0,035 N/mm², produced for example by hydraulic pressure. Under these test conditions, a void content of (25 ± 3) % volume remains in the slag specimen, values conforming to the practice. Alternatively, the sample can be compacted by any other method capable of achieving the same degree of compaction, such as a Proctor hammer or a hand-held power hammer. If water is added to the sample to facilitate compaction, testing shall commence within 24 h of the completion of the compaction process. After compaction, determine the volume of the slag specimen VS, which is the difference between the volume of the cylinder VC and the volume of air VA between the slag specimen and the top edge of the cylinder. Calculate VC and VA from height measurements with the sounding rod (5.18.6) and taking the average of four readings on the extremity of two at right angles crossing diameters plus at minimum four additional readings distributed over the specimen surface. Finally, cover over the surface of the slag specimen with a circular filter (fabric mat) and then with a layer of glass beads (5.18.3) which have been lubricated before the test with silicone oil to reduce friction between the individual beads. Adjust the mass of the layer of beads so that the total mass of the surcharge, the surcharge support, the perforated plate and the glass beads equals (7,5 ± 0,01) kg. Distribute the glass beads evenly within the test cylinder so that they give a level surface. NOTE 2

1,5 g of silicone oil is sufficient for the batch of 1,5 kg of beads.

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Repeat the lubrication of the glass beads after each steam test. As lime is deposited on the glass beads during the steam test, it is furthermore necessary to clean off the lime after every fourth steam test with dilute hydrochloric acid. 19.3.5

Steam test procedure

After the slag test specimen has been covered with the layer of glass beads, attach the test cylinder to the steam equipment and fit the heating jacket to the outer wall of the test cylinder. Then lay the perforated plate, the surcharge support and the surcharge on top of the beads. Adjust the displacement indicator vertically in the centre of the perforated plate and fix it to a rigid support on the steam unit. After switching on the heating jacket and the steam unit, the slag test specimen then starts heating up with an expansion of its volume. In order not to register the lifting movements associated with this, do not begin recording the displacement until steam is passing freely through the sample. The testing time in the steam test depends of the composition of slag. When the MgO content determined in accordance with EN 196-2 is not greater than or equal to 5 %, the testing time shall be 24 h. When the MgO content is more than 5 %, the testing time shall be 168 h. NOTE 1 The total MgO content is used as a measure of free MgO, in the absence, at present of a reliable method of determining the content of free MgO. In the event of a reliable method being developed, the types should be redefined in terms of free MgO content. MgO values declared by steel producers are acceptable for use in determining testing time for steel slag.

At the end of this period the rise in the test specimen surface is read off and calculated in % volume in relation to the original volume (see 19.3.6). The water container in the steam unit normally is of a size that makes it necessary to top up with water during the test. Therefore, care shall be taken to prevent a drop in temperature which would interrupt the production of steam. NOTE 2 In many cases, it is useful to record the development of the increase in volume as dependent on time. As the movements at the beginning of the steam test occur sharply, it is recommended that the movements be read off at intervals of 15 min. After 4 h the interval can be extended to 60 min. If the increase in volume is taken as a function of the time, a detailed interpretation of the test results can be undertaken by means of the graph (starting climb, asymptotic approach to a limit value). For factory production control purposes, it is possible to shorten the test duration by calculating the end point value using regression.

19.3.6


Calculate the volume of the slag test portion VS, before the steam test, from the following equation: VS = VC - VA

(21)

where VS

is the volume of the slag test specimen after compaction in the test cylinder (in mm³);

VC

is the volume of the cylinder (in mm³);

VA

is the volume of air between the slag specimen and the top edge of the cylinder (in mm³);

VC and VA are calculated from the height measurements with the sounding rod and the diameter of the cylinder (210 mm).

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)


After compaction determine the bulk dry density and the void content of the compacted mixture as follows:

ρM =

100 × M ×1 000 and V S × (100 + w)

Va = (1 −

ρM ) ×100 ρ

(22)

(23)

where

ρM

is the bulk density of the compressed mixture (in Mg/m³);

M

is the mass of the compressed mixture (in g);

Va

is the void content of the compressed mixture (in % volume);

VS

is the volume of the slag test specimen after compaction in the test cylinder (in mm³);

ρ

is the pre-dried particle density of the slag, determined as specified in EN 1097-6 (in Mg/m³);

w

is the water content of the sample (in percentage mass).

After completing the test, calculate the expansion in volume % from the rise of the specimen read off the displacement indicator, and from the internal diameter of the test cylinder (210 mm) from the following equation: Expansion =

π × h× d2 4 ×V S

× 100

(24)

where h

is the rise of the specimen after the steam test (in mm);

d

is the internal diameter of the test cylinder (210 mm).

Record the result as the arithmetical mean of the expansion of the two test specimens, rounded to the nearest 0,1 % volume.

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Annex A (informative) Precision

A.1 r1

Symbols is the repeatability limit as defined in EN 932-6.

R1 is the reproducibility limit as defined in EN 932-6. X

is the average of the test results.

A.2 Determination of water-soluble chloride salts using the Volhard method (Reference method) (See Clause 7) The precision of the determination of water-soluble chlorides is stated (in terms of the chloride ion content, as a percentage by mass of the aggregate) as: r1 = 0,000 4 + 0,029 X and R1 = 0,000 6 + 0,124 X

A.3 Determination of water-soluble chloride salts by potentiometry (Alternative method) (See Clause 8) The standard deviation for repeatability r is 0,001 %. The standard deviation for reproducibility R is 0,003 %.

A.4

Determination of water-soluble sulfates in recycled aggregate (See 10.2)

Repeatability r1 and reproducibility R1 have been determined by a French cross testing: two repetitions in eight laboratories. Repeatability r1

=

0,022 + 0,018 X

Reproducibility R1

=

0,047 + 0,016 X

where X is the value T SO4 between 0,2 % and 1 %.

A.5 Determination of total sulfur content by acid digestion (Reference method) (See 11.1) The precision of the determination of total sulfur content is stated (in terms of the sulfur content, as a percentage by mass of the aggregate) as: r1 = 0,017 + 0,081 X and R1 = 0,062 + 0,204 X

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BS EN 1744-1:2009+A1:2012 EN 1744-1:2009+A1:2012 (E)

A.6

Determination of acid soluble sulfates (See Clause 12)


The precision of the determination of acid soluble sulfate content is stated (as the percentage SO3 by mass of the aggregate) as: r1 = 0,021 + 0,200 X and R1 = 0,000 + 0,812 X NOTE

These values were derived using a test portion of 2 g.

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Bibliography

[1]

62 EN 197-1, Cement — Part 1: Composition, specifications and conformity criteria for common cements

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