1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-21528-6 SANS 6242:2008Edition 1.2Any reference to SABS SM 1242 is deemedto be a reference to this standard(Government Notice No. 1373 of 8
4、 November 2002)SOUTH AFRICAN NATIONAL STANDARD Acid insolubility of aggregates Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 6242:2008 Edition
5、 1.2 Table of changes Change No. Date Scope Amdt 1 2002 Amended to update normative references. Amdt 2 2008 Amended to change the designation of SABS standards to SANS standards, and to delete a footnote. Foreword This South African standard was approved by National Committee StanSA SC 5120.61A, Con
6、struction standards Cement, lime and concrete, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in July 2008. This document supersedes SABS SM 1242:2002 (edition 1.1). A vertical line in the margin shows where t
7、he text has been technically modified by amendment No. 2. SANS 6242:2008 Edition 1.2 1 Acid insolubility of aggregates 1 Scope and field of application This standard specifies a method for determining the insolubility of an aggregate when treated with acid. NOTE This property of aggregates is of maj
8、or significance in the production of certain concrete products. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this standard. All standards are subject to revision and, since any reference to a standard is deemed to b
9、e a reference to the latest edition of that standard, parties to agreements based on this standard are encouraged to take steps to ensure the use of the most recent editions of the standards indicated below. Information on currently valid national and international standards can be obtained from Sta
10、ndards South Africa. SANS 197, Preparation of test samples of aggregates. SANS 3310-1/ISO 3310-1, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth. Amdt 1 SANS 3310-2/ISO 3310-2, Test sieves Technical requirements and testing Part 2: Test sieves of perforated me
11、tal plate. Amdt 1 3 Reagents 3.1 Hydrochloric acid Hydrochloric acid, concentrated, analytical reagent. 3.2 Silver nitrate A silver nitrate solution of 1 N in water. 4 Apparatus 4.1 Test sieves, of aperture sizes 600 m and 150 m and that comply with the requirements of SANS 3310-1 or SANS 3310-2. Am
12、dt 1 SANS 6242:2008 Edition 1.2 2 4.2 Filter paper1), medium textured quantitative. Amdt 2 4.3 Platinum crucible, ignited and tared. 5 Preparation of sample 5.1 Take a representative sample of approximately 200 g of the aggregate (see SANS 197) and so crush and mill the sample that it passes a sieve
13、 of aperture size 600 m. Reduce the sample by means of a sample splitter, or by coning and quartering, to obtain a representative portion of approximately 50 g. 5.2 Mill this portion further until it passes a sieve of aperture size 150 m, dry it to constant mass in an oven at a temperature of 100 C
14、to 110 C for 2 h, and then cool it to room temperature in a desiccator. 6 Procedure 6.1 From the material prepared in accordance with 5.1 and 5.2, take a test specimen of approximately 10 g (mass a) place it into a 1 L beaker and add water to make up to a volume of approximately 400 mL and stir well
15、. 6.2 Add 100 mL of hydrochloric acid to the contents of the beaker and again stir well. Heat, breaking up any conglomerated material present, and then boil gently for 10 min while maintaining constant volume. 6.3 Filter through a medium-textured quantitative filter paper (see 4.2), rinse the beaker
16、 with hot water, and finally wash the residue with hot water until the wash water is free from chlorides (i.e. free from cloudiness when tested with silver nitrate). 6.4 Place the paper, with the residue, in a previously ignited and tared platinum crucible (mass b) and carefully char the paper witho
17、ut allowing it to flame. Ignite for 1 h at a temperature of 950 C to 1 000 C, transfer to a desiccator and cool to room temperature. Determine the mass of the crucible and contents to the nearest 0,01 g (mass c). 6.5 Conduct a blank determination, using a previously ignited and tared platinum crucib
18、le (mass d ), following the same procedures as in 6.1 to 6.4 (but excluding the test sample) and using the same quantities of reagents. Determine the mass of the crucible and contents to the nearest 0,01 g (mass e). 1) Whatman No. 40 or equivalent Amdt 2 SANS 6242:2008 Edition 1.2 3 7 Expression and
19、 reporting of results 7.1 Calculate, to the nearest 0,1 %, the insolubility of the aggregate as follows: ()()100cb edawhere c S b is the mass of the residue, in grams (see 6.4); e S d is the mass of the residue found in the blank determination, in grams (see 6.5); and a is the mass of the test sample, in grams (see 6.1). Standards South Africa
