1、August 2010 Translation by DIN-Sprachendienst.English price group 11No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、 59.080.70!$j/“1712912www.din.deDDIN EN ISO 12956Geotextiles and geotextile-related products Determination of the characteristic opening size (ISO 12956:2010)English translation of DIN EN ISO 12956:2010-08Geotextilien und geotextilverwandte Produkte Bestimmung der charakteristischen ffnungsweite (IS
3、O 12956:2010)Englische bersetzung von DIN EN ISO 12956:2010-08Gotextiles et produits apparents Dtermination de louverture de filtration caractristique (ISO 12956:2010)Traduction anglaise de DIN EN ISO 12956:2010-08SupersedesDIN EN ISO 12956:1999-06www.beuth.deIn case of doubt, the German-language or
4、iginal shall be considered authoritative.Document comprises 17 pages08.10 DIN EN ISO 12956:2010-08 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee ISO/TC 221 “Geosynthetics” in collaboration with Technical Committee CEN/TC 189 “Geosyn
5、thetics” (Secretariat: NBN, Belgium). The responsible German body involved in its preparation was the Normenausschuss Textil und Textil-maschinen (Textiles and Textile Machinery Standards Committee), Working Committee NA 106-01-11 AA Geotextilien und Geokunststoffe. The DIN Standards corresponding t
6、o the International Standards referred to in this document are as follows: ISO 9862 DIN EN ISO 9862 ISO 10320 DIN EN ISO 10320 ISO 565 DIN ISO 565 ISO 2591-1 DIN 66165-1, DIN 66165-2 Amendments This standard differs from DIN EN ISO 12956:1999-06 as follows: a) The standard has been editorially revis
7、ed and brought in line with the state of the art. b) Clause 2 “Normative references” has been updated. c) In clause 3, the definition of the symbol of the size of opening has been modified. d) Clause 5 “Apparatus and materials” has been completely revised. e) Subclauses 6.2 and 8.1 have been editori
8、ally revised. f) Clause 9 “Test report” has been editorially revised and Figures 1 and 2 have been replaced. g) Annex B has been editorially revised and Figures B.1 to B.3 have been replaced. Previous editions DIN EN ISO 12956: 1999-06 DIN EN ISO 12956:2010-08 3 National Annex NA (informative) Bibli
9、ography DIN ISO 565, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings DIN 66165-1, Particle size analysis Sieve analysis General principles DIN 66165-2, Particle size analysis Sieve analysis Procedure DIN EN ISO 9862, Geosynthetics Sampling and p
10、reparation of test specimens DIN EN ISO 10320, Geotextiles and geotextile-related products Identification on site DIN EN ISO 12956:2010-08 4 This page is intentionally blank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 12956 April 2010 ICS 59.080.70 Supersedes EN ISO 12956:1999English Ve
11、rsion Geotextiles and geotextile-related products - Determination of the characteristic opening size (ISO 12956:2010) Gotextiles et produits apparents - Dtermination de louverture de filtration caractristique (ISO 12956:2010) Geotextilien und geotextilverwandte Produkte - Bestimmung der charakterist
12、ischen ffnungsweite (ISO 12956:2010) This European Standard was approved by CEN on 22 March 2010. 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
13、-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN 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 unde
14、r the responsibility of a CEN member into its own language and notified to the CEN 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, France, Germany,
15、 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 STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Man
16、agement Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 12956:2010: EContents DIN EN ISO 12956:2010-08 EN ISO 12956:2010 (E) 2 Page Foreword3 1 Scope 4 2 Normative references 4 3 S
17、ymbols 4 4 Principle4 5 Apparatus and materials.5 6 Test specimens6 6.1 Handling6 6.2 Selection .6 6.3 Number and dimensions.6 6.4 Specimen condition.6 7 Procedure .6 8 Calculation and expression of results.7 9 Test report 7 Annex A (normative) Mesh sizes .10 Annex B (informative) Example of the det
18、ermination of the characteristic opening size .11 Foreword This document (EN ISO 12956:2010) has been prepared by Technical Committee ISO/TC 221 which is held by NBN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement
19、, at the latest by October 2010, and conflicting national standards shall be withdrawn at the latest by October 2010. 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
20、 any or all such patent rights. This document supersedes EN ISO 12956:1999. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). According to the CEN/CENELEC Internal R
21、egulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg,
22、 Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 12956:2010 has been approved by CEN as a EN ISO 12956:2010 without any modification. “Geosynthetics” in collaboration with Technical Commi
23、ttee CEN/TC 189 “Geosynthetics”, the secretariat of DIN EN ISO 12956:2010-08 EN ISO 12956:2010 (E) 3 1 Scope This International Standard specifies a method for the determination of the characteristic size of the openings of a single layer of a geotextile or geotextile-related product using the wet-s
24、ieving principle. 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. ISO 9862
25、, Geosynthetics Sampling and preparation of test specimens ISO 10320, Geotextiles and geotextile-related products Identification on site ISO 565, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings ISO 2591-1, Test sieving Part 1: Methods using test
26、 sieves of woven wire cloth and perforated metal plate 3 Symbols For the purposes of this document, the following symbols apply. 3.1 dnparticle size for which n % mass fraction is smaller than the mass of measured particles 3.2 O90size of opening which is equal to the particle of size d90of the gran
27、ular material which passes through the geotextile or geotextile-related product 3.3 Cucoefficient of uniformity, defined as d60/d104 Principle The particle size distribution of a graded granular material (usually soil) is determined after washing through a single layer of the geotextile or geotextil
28、e-related product used as a sieve, without load. The characteristic opening size corresponds to a specified size of the granular material passed. DIN EN ISO 12956:2010-08 EN ISO 12956:2010 (E) 4 5 Apparatus and materials 5.1 Sieving apparatus, composed of the following elements. 5.1.1 Sieving unit,
29、allowing for the testing of a specimen with an exposed sieving area corresponding to a minimum diameter of 130 mm, complying with the following requirements: a) sieving device, with a frequency of 50 Hz to 60 Hz; b) predominantly vertical sieve motion capable of maintaining a 1,5 mm amplitude (3 mm
30、swing height) over the period of test. 5.1.2 Water supply system. 5.1.3 Spray nozzle(s), to ensure even wetting of the test specimen, enclosed in a transparent cylinder or covering cap to avoid soil or granular material loss; It is recommended that the nozzle(s) be capable of a water discharge of ap
31、proximately 0,5 l/min at a working pressure of about 300 kPa. 5.1.4 Specimen clamping device. 5.1.5 Pan, affixed to the sieving apparatus, with a tube connection to the device for collection of the water and granular material passing through the specimen. NOTE Typical sieving equipment is represente
32、d in Figure 1. 5.1.6 Grid, with wire of 1 mm in diameter and a mesh size of (10 1) mm to support the specimen during the test, to avoid excessive deformation of the specimen under the weight of the granular material. 5.2 Granular material, complying with the following requirements: a) It should be c
33、ohesion-less, i.e. particles shall not aggregate in water. If there is no visible agglomeration of particles during the test, the results are acceptable. If not, the test has to be performed again. b) It shall not be gap-graded and the particles shall be essentially round, and sharp-edged flaky part
34、icles shall be avoided. c) 3 u Cuu 20. d) To improve the accuracy of the characteristic opening size determination, the granular material shall be such that d20u O90u d80; the zone for the graded granular material and the range of O90values which are applicable are given in Figure 2. 5.3 Filter pape
35、r, to collect the passed granular material. If the graded material contains a silt fraction, the filter paper used should have a maximum opening size of 10 m. 5.4 Drying oven, capable of maintaining temperatures of between 50 C and 110 C. 5.5 Set of sieves, in accordance with ISO 565, size R 20 (see
36、 Annex A). 5.6 Balance, for determining the mass of the granular to an accuracy of 0,03 g. 5.7 Stopwatch, for measuring time to an accuracy of 1 s. DIN EN ISO 12956:2010-08 EN ISO 12956:2010 (E) 5 6 Test specimens 6.1 Handling The sample shall be handled as infrequently as possible and shall not be
37、folded, in order to prevent disturbing its structure. Keep the sample in a flat position without any load. 6.2 Selection Take specimens from the sample in accordance with ISO 9862. 6.3 Number and dimensions Cut five test specimens from the sample, each of the dimensions suitable for the sieve appara
38、tus to be used. 6.4 Specimen condition The specimens shall be clean, free from surface deposits and without visible damage or folding marks. 7 Procedure 7.1 Determine and record the mass of the dry specimen to the nearest 0,1 g. The specimen is considered dry when there is a reduction in mass of les
39、s than 0,1 % between consecutive measurements with a time interval of 600 s. Drying should be carried out at a temperature of 70 C or less, if the temperature affects the material. 7.2 Place the specimen under water containing a wetting agent at laboratory temperature and leave it to saturate for at
40、 least 12 h. The wetting agent used shall be an aryl alkyl sulfonate at 0,1 % volume. 7.3 Remove the specimen from the water and place it flat and without tension in the clamping device. Place the clamping device on the sieving apparatus. The specimen should be horizontal to avoid accumulation of gr
41、anular material at one location on the specimen. 7.4 Determine the dry mass of the granular material to the nearest 0,1 g. Use enough granular material to achieve a mass per specimen equivalent to (7,0 0,1) kg/m2of exposed sieving area. However, if the amount passing during the test is insufficient,
42、 the total amount can be adapted in such a way that enough material is passed to carry out a particle size analysis. 7.5 Spread the granular material evenly on the specimen. 7.6 Open the water supply and spray water uniformly over the whole specimen. Adjust the quantity of water with a regulating va
43、lve to ensure that granular particles are completely wetted, but do not allow the water level to rise above the granular material. There shall be no standing water on the specimen. Maintain the water supply during the whole sieving operation. 7.7 Switch on the sieving device and slowly adjust the am
44、plitude to 1,5 mm (3 mm swing height). 7.8 Collect the granular material which passes through the specimen. 7.9 After a sieving time corresponding to 600 s, switch off the sieving device and turn off the water supply. 7.10 Collect the specimen together with any retained granular material. 7.11 Dry,
45、separately, the passed granular materials (see 7.8) and the specimen with the retained granular material (see 7.10). 7.12 Obtain the dry mass of the retained granular material by weighing the specimen containing the retained granular material and subtracting the dry mass of the specimen. Determine t
46、o an accuracy of 0,1 g the dry mass of the retained granular material. Determine, also, the dry mass of the passed granular material. If the combined mass of the retained and passed granular material deviates more than 1 % from the initial total dry mass, the test is invalid and shall be repeated. D
47、IN EN ISO 12956:2010-08 EN ISO 12956:2010 (E) 6 7.13 Repeat 7.1 to 7.12 until three of the five specimens have been tested. 7.14 If any of the masses of granular materials passing through the specimen vary from the average by more than 25 %, then the two remaining specimens shall be tested. 7.15 Tab
48、ulate the initial amount of granular material, the material passed and retained, and calculate the percentages of material passed and lost as indicated in Table 1 or Table 2. Combine the granular material passed through the individual specimens and determine the particle size distribution. NOTE Afte
49、r selection of the required successive sieves as given in ISO 565, size R 20 (see Annex A), guidance for the determination of the particle size distribution of the granular material, by sieving is given in ISO 2591-1. An example is given in Annex B. 7.16 If the amount of the passed granular material of three specimens is less than the amount required for sieving in accordance with ISO 2591-1, the two remaining specimens shall be tested and Table 2 completed. If the additional testing does not produce the required amount o
