1、BRITISH STANDARDBS EN 1744-5:2006Tests for chemical properties of aggregates Part 5: Determination of acid soluble chloride saltsThe European Standard EN 1744-5:2006 has the status of a British StandardICS 91.100.15g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g5
2、4g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 1744-5:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 September 2007 BSI 2007ISBN 978 0 580 53746 2National forew
3、ordThis British Standard is the UK implementation of EN 1744-5:2006.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 committee can be obtained on request to its secretary.
4、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.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME
5、EUROPENNEEUROPISCHE NORMEN 1744-5October 2006ICS 91.100.15English VersionTests for chemical properties of aggregates - Part 5:Determination of acid soluble chloride saltsEssais pour dterminer les proprits chimiques desgranulats - Partie 5: Dtermination de la teneur enchlorures solubles dans lacidePr
6、fverfahren fr chemische Eigenschaften vonGesteinkrnungen - Teil 5: Bestimmung der surelslichenChlorideThis European Standard was approved by CEN on 28 August 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard
7、 the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, Germa
8、n). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark
9、, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUR
10、OPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 1744-5:2006: EEN 1744-5:2006 (E) 2 Contents page Foreword. 3 1 Scope 4 2 Normative references . 4
11、3 Definitions 4 4 Reagents 4 4.1 General requirements for densities 5 4.2 Reagents for determination of acid -soluble chloride salts (Volhard method) 5 5 Apparatus 6 6 Principle . 6 7 Sampling 6 8 Preparation of test portion. 6 9 Procedure 7 10 Calculation and expression of results 7 11 Test report
12、. 7 Bibliography . 8 EN 1744-5:2006 (E) 3 Foreword This document (EN 1744-5:2006) 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
13、 text or by endorsement, at the latest by April 2007, and conflicting national standards shall be withdrawn at the latest by April 2007. This standard forms part of a series of tests for chemical properties of aggregates. Test methods for other properties of aggregates will be covered by Parts of th
14、e following European Standards: EN 932 Tests for general properties of aggregates EN 933 Tests for geometrical properties of aggregates EN 1097 Tests for mechanical and physical properties of aggregates EN 1367 Tests for thermal and weathering properties of aggregates EN 13179 Tests for filler aggre
15、gate used in bituminous mixtures The other parts of EN 1744 are, or will be: Part 1: Chemical analysis Part 2: Determination of resistance to alkali reaction Part 3: Preparation of eluates by leaching of aggregates Part 4: Determination of water susceptibility of fillers for bituminous mixtures Part
16、 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 organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Rep
17、ublic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 1744-5:2006 (E) 4 1 Scope This European Standard sp
18、ecifies the procedure for the determination of acid soluble chloride salts which may be present in aggregates. This test is suitable for aggregates where the chloride content does not derive directly from contact with, or immersion in, saline water. Examples of such aggregates are: recycled aggregat
19、es containing hydrated cement, where chloride may be bound as calcium chloroaluminates; and some aggregates from desert areas where chloride is occluded within the aggregate particles. 2 Normative references The following referenced documents are indispensable for the application of this European St
20、andard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1744-1:1998, Tests for chemical properties of aggregates Part 1: Chemical analysis EN 932-1, Tests for general properties of aggr
21、egates Part 1: Methods for sampling EN 932-5, Tests for general properties of aggregates Part 5: Common equipment and calibration ISO 384, Laboratory glassware Principles of design and construction of volumetric glassware ISO 1042:1983, Laboratory glassware One-mark volumetric flasks 3 Definitions F
22、or the purposes of this standard, the following terms and definitions apply. 3.1 test portion sample used as a whole in a single test 3.2 test specimen when a test method requires more than one determination of a property, the test specimen is the sample used in a single determination 3.3 laboratory
23、 sample reduced sample derived from a bulk sample for laboratory testing 4 Reagents Unless otherwise stated, use only analytical grade reagents and demineralised water, or water of equivalent purity. NOTE 1 Unless otherwise stated “%“ means “% by mass“. NOTE 2 Where no tolerances are given for reage
24、nt volumes or masses, the values quoted are approximate. In such cases volumes delivered from measuring cylinders and indicated masses using the ordinary balance specified in 5.1 are considered sufficiently accurate for the purposes of this European Standard. NOTE 3 Unless otherwise stated reagent s
25、olutions may be assumed to have long-term stability. EN 1744-5:2006 (E) 5 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 atte
26、ntion should be maintained. 4.1 General requirements for densities The following concentrated liquid reagents required by this standard shall have the following densities in grams per cubic centimetre at (20 3) C. Hydrochloric acid : 1,18 to 1,19 Nitric acid : 1,40 to 1,42Sulfuric acid : 1,84 Ammoni
27、um hydroxide : 0,88 to 0,91 The degree of dilution shall be indicated as a volumetric sum. NOTE Ready for use solutions are allowed as an alternative. 4.2 Reagents for determination of acid -soluble chloride salts (Volhard method) 4.2.1 Silver nitrate (AgNO3) solution: 0,100 mol/l is prepared by dry
28、ing about 20 g of silver nitrate for at least 1 h at a temperature of (110 5) C, allowing it to cool in a dessicator, weighing (16,987 0,001) g of the dried silver nitrate, then dissolving it in water and diluting it to 1 l in a volumetric flask (5.6). Store the solution in the amber-coloured glass
29、reagent bottle (5.7) and protect from prolonged exposure to sunlight. 4.2.2 Thiocyanate (KSCN or NH4SCN) solution: approximately 0,1 mol/l is prepared by dissolving 9,7 g of potassium thiocyanate or 7,6 g of ammonium thiocyanate in water and diluting it to 1 l in a volumetric flask. Pipette 25 ml of
30、 silver nitrate solution (4.2.1) into a flask (5.8) 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 (5.9) until the first permanent colour change occurs, that is from white opalescence to pale brown.
31、Note the volume of thiocyanate solution (V0) added. Calculate the concentration of the thiocyanate solution cT, (in moles per litre), from the following equation: cT= 2,5/V0 (1) where V0is the volume of thiocyanate added (in millilitres). Standardize the solution at weekly intervals or before use if
32、 the tests are carried out infrequently. 4.2.3 Nitric acid (HNO3): approximately 6 mol/l is prepared by adding 100 ml of nitric acid (4.1) to 150 ml of water, boiling the diluted acid in a fume cupboard (5.11) until it is colourless and allowing to cool to room temperature. 4.2.4 Chloride free techn
33、ical grade 3,5,5,-trimethylhexan-1-ol. 4.2.5 Ammonium iron (III) sulfate NH4Fe(SO4)2.12H2O indicator solution is prepared by adding 60 g of water to 50 g of ammonium iron (III) sulfate, warming until it dissolves, and adding 10 ml of nitric acid (4.2.3). Allow the solution to cool to room temperatur
34、e and store it in a glass bottle (5.10). EN 1744-5:2006 (E) 6 5 Apparatus All apparatus shall comply with the general requirements of EN 932-5. All volumetric glassware shall be of class B accuracy as defined in ISO 384. Volumetric glassware of class A shall be used for audit test and type test. 5.1
35、 Balance, capable of weighing up to 100 g, readable to the nearest 0,1 mg. 5.2 Two filter funnels, of approximately 100 mm diameter with coarse filter papers (pore diameter approximately 20 m); of diameters appropriate to the size of the funnels. 5.3 Two 250 ml beakers. 5.4 Glass rods. 5.5 Pipette:
36、1 ml, 5 ml, 25 ml 5.6 Two volumetric flasks, capacity of 1 l, complying with the requirements of ISO 1042. 5.7 Amber-coloured glass reagent bottles. 5.8 Stoppered conical flasks, 100 ml and 250 ml capacity. 5.9 Burette, 50 ml size, graduated to 0,1 ml. 5.10 Plain glass reagent bottles. 5.11 Fume cup
37、board. 6 Principle This method gives the total halide content except for fluoride and expresses the result as chloride ion content. The aggregate sample is reduced to a fine powder and extracted with boiling dilute nitric acid. NOTE Sulfides are oxidised into sulfates and do not interfere. The disso
38、lved chloride is precipitated using a known volume of standard silver nitrate solution. After boiling, the precipitate and the remaining solid aggregate are washed with a dilute nitric acid and discarded. The filtrate and washings are cooled to room temperature and the residual silver nitrate is tit
39、rated with a standard thiocyanate solution using an iron (III) salt as an indicator (Volhard method). 7 Sampling The laboratory sample shall be taken in accordance with the procedures specified in EN 932-1. Ensure that the laboratory sample is representative of the moisture content as well as the so
40、lids. 8 Preparation of test portion The test specimen is prepared using the procedure given in EN 1744-1:1998, 12.3. Take approximately 2 g of the powdered sample as the test specimen. EN 1744-5:2006 (E) 7 9 Procedure Weigh the test specimen to the nearest 0,1 mg and record it as “m”; place it in a
41、250 ml beaker, add 50 ml of water and while stirring with a glass rod, 50 ml of dilute nitric acid (1 + 2). Heat the mixture to boiling, stirring occasionally, and boil for 1 min. NOTE Aggregates containing significant amounts of carbonates will froth on addition of the acid. In these cases, add the
42、 acid slowly while continuously stirring. Add 5 ml of the 0,100 mol/l silver nitrate solution by pipette (5.5) into the boiling solution. Then boil for a maximum of 1 min and filter through a filter paper (5.2) washed before use with dilute nitric acid (1 + 100) into a 500 ml flask (5.6). Wash the b
43、eaker, glass rod and filter with dilute nitric acid (1 + 100) until the volume of filtrate and washings is 200 ml. Cool the filtrate and washings to room temperature. Add 5 ml ammonium iron (III) sulfate indicator solution and titrate with the thiocyanate solution, shaking vigorously until a drop of
44、 this solution produces a faint brown coloration which no longer disappears on shaking. Note the volume V1of the thiocyanate solution added. If the chloride content of the aggregate exceeds 0,85 %, it will be necessary to start the test again with a smaller test portion. Repeat the procedure with a
45、second test specimen. 10 Calculation and expression of results Calculate the chloride content (in %) from the following equation: Ca =3,545 x (5-10 CT V1)/1000 x 100/m = 0,3545(5-10 CT V1)/m (2) where: m is the mass of the test portion (in grams); V1 is the volume of thiocyanate solution used for th
46、e titration of the test solution (in millilitres); CTis the concentration of the thiocyanate solution (in moles/litre, see 4.2.2). The result of the test is given as the mean of the determinations on the two test specimens, and recorded to the nearest 0,01 %. 11 Test report a) reference to this Euro
47、pean Standard; b) source of the sample; c) designation of the sample; d) mass of dry sample tested, (in grams); e) result of the test; f) date of the test. EN 1744-5:2006 (E) 8 Bibliography 1 EN 196-21:1989, Methods of testing cement: Determination of the chloride, carbon dioxide and alkali content
48、of cement. 2 EN 932-2: 1999, Test for general properties of aggregates Methods of reducing laboratory samples. blankBS EN 1744-5:2006BSI389 Chiswick High RoadLondonW4 4ALBSI British Standards InstitutionBSI is the independent national body responsible for preparing British Standards. It presents the
49、 UK view on standards in Europe and at the international level. It is incorporated by Royal Charter.RevisionsBritish Standards are updated by amendment or revision. Users of British Standards should make sure that they possess the latest amendments or editions.It is the constant aim of BSI to improve the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the identity of which can be f
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