BS EN ISO 10769-2011 Clay geosynthetic barriers Determination of water absorption of bentonite《粘土土工合成材料屏障 膨润土吸水性测定》.pdf

1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 10769:2011Clay geosynthetic barriers Determination of water absorption of bentonite (ISO 10769:2011)BS EN ISO 10769:2011 BRITISH STANDARDNational forewordThis British S

2、tandard is the UK implementation of EN ISO 10769:2011.BSI, as a member of CEN, is obliged to publish EN ISO 10769:2011 as a British Standard. However, attention is drawn to the fact that during the development of this Standard, the UK committee voted against its approval as a European Standard.The U

3、K committee has concerns about the reproducibility of this test. It believes that the test was originally designed for materials of a low water absorption rate such as calcium bentonite, not sodium bentonite, which has a higher water absorption rate.The UK participation in its preparation was entrus

4、ted to Technical Committee B/553, Geotextiles and geomembranes.A list of organizations represented on this committee 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.

5、 BSI 2011 ISBN 978 0 580 61350 0 ICS 59.080.70 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 July 2011.Amendments issued since publicationDate Text affected

6、EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 10769 June 2011 ICS 59.080.70 English Version Clay geosynthetic barriers - Determination of water absorption of bentonite (ISO 10769:2011) Gosynthtiques bentonitiques - Dtermination de labsorption deau par la bentonite (ISO 10769:2011) Geosynt

7、hetische Tondichtungsbahnen (GBR-C) - Bestimmung der Wasseraufnahme von Bentonit (ISO 10769:2011) This European Standard was approved by CEN on 31 May 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the

8、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

9、, 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, C

10、roatia, Cyprus, Czech Republic, 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. EUROPEAN COMMITTEE FOR STANDA

11、RDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 10769:2011: EBS EN ISO 10769:2011 EN ISO 10769:20

12、11 (E) 3 Foreword This document (EN ISO 10769:2011) has been prepared by Technical Committee ISO/TC 221 “Geosynthetics“ in collaboration with Technical Committee CEN/TC 189 “Geosynthetics” the secretariat of which is held by NBN. This European Standard shall be given the status of a national standar

13、d, either by publication of an identical text or by endorsement, at the latest by December 2011, and conflicting national standards shall be withdrawn at the latest by December 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.

14、 CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cypr

15、us, Czech Republic, 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 the United Kingdom. Endorsement notice The text of ISO 10

16、769:2011 has been approved by CEN as a EN ISO 10769:2011 without any modification. BS EN ISO 10769:2011ISO 10769:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv 1 Scope1 2 Normative references1 3 Terms and definitions .1 4 Principles2 5 Apparatus.2 6 Preparation and size of specime

17、ns .2 7 Procedures.2 7.1 Preparation of the equipment 2 7.2 Test procedure.3 8 Test report3 Annex A (informative) Water content diagram.7 BS EN ISO 10769:2011ISO 10769:2011(E) iv ISO 2011 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation o

18、f national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. In

19、ternational organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with

20、the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval

21、 by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 10769 was prepared by Technical Committee

22、ISO/TC 221, Geosynthetics. BS EN ISO 10769:2011INTERNATIONAL STANDARD ISO 10769:2011(E) ISO 2011 All rights reserved 1Clay geosynthetic barriers Determination of water absorption of bentonite 1 Scope This International Standard specifies a method for determining the water absorption of bentonite. Th

23、e bentonite component is a part of clay geosynthetic barriers (GBR-C). Water absorption depends on the specific surface of the fine particles and the surface activity of the bentonite. The test provides an index value for production control testing of GBR-C. 2 Normative references The following refe

24、renced 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. ISO 3310-1, Test sieves Technical requirements and testing Part 1:

25、Test sieves of metal wire cloth ISO 4793:1980, Laboratory sintered (fritted) filters Porosity grading, classification and designation ISO 11465, Soil quality Determination of dry matter and water content on a mass basis Gravimetric method DIN 18132, Soil, testing procedures and testing equipment Det

26、ermination of water absorption 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 water absorption wAratio of the mass of water, mwg, absorbed by the dry bentonite specimen in the test apparatus to the dry mass, md, of the bentonite specimen NOT

27、E 1 wgAd= mwmwhere mwgis the limiting value of the absorbed water absorbed over the test period. NOTE 2 The result may also be expressed as the proportion by mass, in %. BS EN ISO 10769:2011ISO 10769:2011(E) 2 ISO 2011 All rights reserved4 Principles The amount of water absorbed in relation to the d

28、ry mass of the bentonite sample is determined over time by an automatic electronic balance system. The water absorption value, wA, is determined during a test period of 24 hours. Different bentonite samples can be compared using water content diagrams (see Annex A). 5 Apparatus The following apparat

29、us shall be used. 5.1 Drying oven. 5.2 Water absorption device (based on DIN 18132, for details see Figure 1), consisting of a glass top tube with glass filter plate to support the specimen; a glass connection tube and glass measurement tube with a 2 ml nominal volume; the glass measurement tube is

30、positioned horizontally such that the measurement tube axis is 50 mm lower than the surface of the glass filter plate; the filter plate shall be clean and without contamination; the glass top tube shall be cleaned after 50 test uses (e.g. in an ultrasonic bath) or replaced. 5.3 Mortar and pestle or

31、ball mill. 5.4 Desiccator jar. 5.5 Filling funnel with short stem see Figure 1 c), inserted into the glass top tube. The outlet of the glass funnel shall be 20 mm above the glass filter plate. 5.6 Glass stopper (see Figure 2). 5.7 Weighing paper (smooth laboratory paper), for use when filling the sp

32、ecimen. 5.8 Electronic balances, with computer interface. The resolution shall be 0,001 g. 5.9 Metal test sieves, with 250 m mesh size in accordance with ISO 3310-1. 5.10 Computer. 6 Preparation and size of specimens Sieve the sample of bentonite through a 250 m mesh size sieve to remove particles g

33、reater than 250 m. Grind all removed particles over 250 m to a particle size less than 250 m and resieve them. Dry the passed material in the oven at a temperature of (60 3) C until it has reached a constant mass in accordance with ISO 11465. Cool the sample to room temperature in a desiccator. The

34、dry mass of the specimen shall be approximately 0,25 g with no particles greater than 250 m. Determine the mass of the specimen with a resolution of 0,001 g. 7 Procedures 7.1 Preparation of the equipment The inside surfaces of the individual items of glass equipment shall be clean. In order to avoid

35、 wetting errors, the glass measurement tube shall be cleaned before the start of the test and flushed several times with demineralised water. BS EN ISO 10769:2011ISO 10769:2011(E) ISO 2011 All rights reserved 3The glass measurement tube (3), glass connection tube (2) and glass top tube (4) including

36、 the part above the glass filter plate are all fitted together as shown in Figure 1 in such a way that the ground conical joints are sealed, and filled with demineralised, deaired water, free of entrapped air and bubbles. The glass measurement tube shall be horizontal. The water level in the glass t

37、op tube is now set to the height of the glass filter plate surface. Any droplet attached to the point of the glass measurement tube shall be swabbed off. The inside wall of the glass top tube shall be dried above the glass filter plate by swabbing off the water. For the calibration, the equipment sh

38、all be weighed without specimen for a period of 24 h. Repeat the preparation if the mass is not constant after 24 h with a resolution of 0,03 g. 7.2 Test procedure Connect the interface of the electronic balance with the computer to establish a mass variation over time. The specimen is placed on the

39、 glass filter plate using the glass funnel. The glass funnel outlet shall be placed centrally over the glass filter plate in the glass top tube in order to obtain a reproducible, conical test specimen on the glass filter plate. The test specimen shall be passed into the glass funnel using a smooth l

40、aboratory paper folded in the middle. The glass top tube shall be plugged with a glass stopper (see Figure 2). The test period begins when the first particles of bentonite fall on the filter plate. The mass of the absorbed water is measured by the electronic balance and recorded by the computer. The

41、 duration of the test is 24 h. A second electronic balance may be utilized to control and calibrate the first electronic balance. 8 Test report The test report shall include the following information: a) the reference number and year of publication of this International Standard (i.e. ISO 10769:2011

42、); b) the identification of the sample, date of receipt and date of testing; c) the mass of the fraction particle size lower than 250 m; d) the room temperature; e) the water absorption, wA; f) a water content diagram, the water contents of bentonite shall be shown in a diagram in relation to the te

43、st time, where abscissa time to a logarithmic scale, ordinate water content to a linear scale; g) any deviation from this procedure. BS EN ISO 10769:2011ISO 10769:2011(E) 4 ISO 2011 All rights reservedDimensions in millimetres 31097462815a) Test fixture 4660557160 5502030b) Details of glass top tube

44、, glass connection tube and funnel Figure 1 (continued) BS EN ISO 10769:2011ISO 10769:2011(E) ISO 2011 All rights reserved 565 1 20,8 135 5 60c) Details of funnel Key 1 stand 2 glass connection tube with ground female joint and ground male joint, axis of the ground conical joints arranged at right a

45、ngles to one another 3 glass measurement tube 4 glass top tube with ground female joint and ground conical joint and glass filter plate, (porosity P 100, thickness 3 mm) in accordance with ISO 4793:1980, sealed in at right angles to the top tube pipe axis and at a distance of 50 mm from the measurem

46、ent tube axis 5 stand clamp for glass funnel (6) 6 funnel with short stem and smooth inside surface 7 specimen cone 8 balance 9 hose 10 inspection balance Figure 1 Modified water absorption device based on Enslin/Neff method BS EN ISO 10769:2011ISO 10769:2011(E) 6 ISO 2011 All rights reservedDimensi

47、ons in millimetres 29321Figure 2 Glass stopper with ground conical joint and capillary opening BS EN ISO 10769:2011ISO 10769:2011(E) ISO 2011 All rights reserved 7Annex A (informative) Water content diagram 0 10 100 1 000 10 000 100 000050100150200250300350400XY24 hKey X time (s) Y water content (%)

48、 Figure A.1A. Sample for a water content diagram This page deliberately left blankThis page deliberately left blankBSI is the independent national body responsible for preparing British Standardsand other standards-related publications, information and services. It presents the UK view on standards

49、in Europe and at the international level. It is incorporated by Royal Charter.British Standards Institution (BSI)raising standards worldwideBSI Group Headquarters389 Chiswick High Road London W4 4AL UKTel +44 (0)20 8996 9001Fax +44 (0)20 8996 Standards are updated by amendment or revision. Users of British Stan-dards should make sure that they possess the latest amendments or editions.It is the constant aim of BSI to improve the