1、BRITISH STANDARD BS EN ISO 13426-2:2005 Geotextiles and geotextile-related products Strength of internal structural junctions Part 2: Geocomposites The European Standard EN ISO 13426-2:2005 has the status of a British Standard ICS 59.080.70 BS EN ISO 13426-2:2005 This British Standard was published
2、under the authority of the Standards Policy and Strategy Committee on 6 September 2005 BSI 6 September 2005 ISBN 0 580 46188 2 National foreword This British Standard is the official English language version of EN ISO 13426-2:2005. It is identical with ISO 13426-2:2005. The UK participation in its p
3、reparation was entrusted to Technical Committee B/553, Geosynthetics, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in t
4、his document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a c
5、ontract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposal
6、s for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, the EN ISO foreword page, the ISO title page, pages ii to iv, pag
7、es 1 to 10, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Reference number ISO 13426-2:2005(E)INTERNATIONAL STANDARD ISO 13426-2 First edition 2005-04-
8、15 Geotextiles and geotextile-related products Strength of internal structural junctions Part 2: Geocomposites Gotextiles et produits apparents Rsistance des liaisons de structures internes Partie 2: Gocomposites EN ISO 13426-2:2005 ii EN ISO 13426-2:2005 EN ISO 13426-2:2005 iiiContents Page Forewor
9、d iv 1 Scope 1 2 Normative references . 1 3 Terms and definitions. 1 4 Principle . 2 5 Conditioning atmosphere. 3 6 Number of specimens to be tested . 3 7 Test specimens . 3 8 Apparatus. 5 9 Test procedure 5 10 Calculations. 6 11 Test report 7 Bibliography . 10 EN ISO 13426-2:2005 iv Foreword ISO (t
10、he International Organization for Standardization) is a worldwide federation of 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 commit
11、tee has been established has the right to be represented on that committee. International 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 electrotech
12、nical standardization. International Standards are drafted in accordance with 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
13、 bodies for voting. Publication as an International Standard requires approval 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
14、 any or all such patent rights. ISO 13426-2 was prepared by the European Committee for Standardization (CEN) Technical Committee CEN/TC 189, Geosynthetics, in collaboration with Technical Committee ISO/TC 221, Geosynthetics, in accordance with the Agreement on technical cooperation between ISO and C
15、EN (Vienna Agreement). ISO 13426 consists of the following parts, under the general title Geotextiles and geotextile-related products Strength of internal structural junctions: Part 1: Geocells Part 2: Geocomposites Part 3: Geogrids 1Geotextiles and geotextile-related products Strength of internal s
16、tructural junctions Part 2: Geocomposites 1 Scope This part of ISO 13426 describes index tests for determining the strength of the internal structural junctions of all geocomposites and of clay geosynthetic barriers. 2 Normative references The following referenced documents are indispensable for the
17、 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 554, Standard atmospheres for conditioning and/or testing Specifications ISO 9862, Geosynthetics Sampling
18、 and preparation of test specimens ISO 10318, Geosynthetics Terms and definitions 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 10318 and the following apply. 3.1 failure point at which a geosynthetic ceases to be functionally capable of its intend
19、ed use NOTE A material may be considered to have failed without rupture. 3.2 geocomposite manufactured, assembled material using at least one geosynthetic product among the components, used in contact with soil and/or other materials in geotechnical and civil engineering applications 3.3 junction po
20、int or line where two of the geosynthetics components are connected 3.4 junction strength peak load attained during the test, reported to the unit width of the product NOTE The junction strength is expressed in kilonewtons per metre (kN/m). EN ISO 13426-2:2005 2 3.5 peel test tensile test where two
21、components of a geocomposite are separately clamped and one component is peeled away from the other 3.6 rupture breaking or tearing apart of a geosynthetic 3.7 shear test tensile test where two components of a geocomposite are separately clamped and the failure occurs along the plane of the product
22、4 Principle Specimens are tested to measure the resistance of the junctions to different states of stress. The tests performed for geocomposites are as follows: Shear test (Test A Figure 1): After cutting a test specimen of wide width, one of the two geosynthetics making the junction is delaminated
23、from the other for a certain length at each opposed edge, enough to ensure a good clamping. The delaminated portion is mounted in a clamp of a tensile testing machine, while the other geosynthetic at the opposite edge of the specimen is mounted in the other clamp. The specimen is tested at a constan
24、t rate of strain, until shear failure of the junction or tensile failure of one of the geosynthetics occurs. The corresponding tensile shear resistance is measured and recorded. Peel test (Test B Figure 2): After cutting a a test specimen of wide width, one of the two geosynthetics making the juncti
25、on is delaminated from the other for a certain length at one edge, enough to ensure a good clamping. The delaminated portions of the two geosynthetics are each mounted in one clamp of a tensile testing machine. The specimen is tested until failure occurs. The corresponding peeling resistance is meas
26、ured and recorded. Dimensions in millimetres Key 1 clamp 2 first geosynthetic component 3 second geosynthetic component Figure 1 Shear test EN ISO 13426-2:2005 3Dimensions in millimetres Key 1 clamp 2 first geosynthetic component 3 second geosynthetic component Figure 2 Peel test 5 Conditioning atmo
27、sphere The test specimens shall be conditioned in the standard atmosphere for testing at (20 2) C and (65 5) % relative humidity, as defined in ISO 554. The specimens can be considered to be conditioned when the change in mass in successive weighings made at intervals of not less than 2 h does not e
28、xceed 0,25 % of the mass of the test specimen. Conditioning and/or testing in a standard atmosphere may only be omitted when it can be shown that results obtained for the same specific type of product (both structure and polymer type) are not affected by changes in temperature and humidity exceeding
29、 these limits. This information shall be included in the test report. 6 Number of specimens to be tested Five specimens shall be tested for each product for each of the machine and cross-machine directions and for each structural junction (if the geocomposite is made up of three or more different la
30、yers of geosynthetics and/or mineral materials). 7 Test specimens 7.1 Selection of test specimens Take specimens in accordance with ISO 9862. 7.2 Dimension of test specimens Cut specimens according to the shapes and dimensions shown in Figures 3 and 4, respectively for Tests A or B. To monitor slipp
31、age and to make sure the applied force remains parallel to the longitudinal axis of the specimen, draw two lines on the full width of the test specimen. These lines shall be parallel to each other, EN ISO 13426-2:2005 4 perpendicular to the test direction and at equal distances from the edges of the
32、 specimen. Their distance from each other shall be (155 2) mm for Test A and (95 2) mm for Test B. For specimens having discrete structural junctions (i.e. welded points, stitching), it may be necessary to increase the dimensions of the test specimen to include at least one complete junction. Care s
33、hall be taken, when delaminating one geosynthetic from the other, not to change or reduce the characteristics of the junction. Dimensions in millimetres Key 1 first geosynthetic component 2 second geosynthetic component L is the laminated part D is the delaminated part Lo is the length of the lamina
34、ted part Ld is the length of the delaminated part Figure 3 Shear test specimen Dimensions in millimetres Key 1 first geosynthetic component 2 second geosynthetic component L is the laminated part D is the delaminated part Lo is the length of the laminated part Ld is the length of the delaminated par
35、t Figure 4 Peel test specimen EN ISO 13426-2:2005 58 Apparatus 8.1 Tensile testing machine This is a tensile testing machine with a constant rate of extension, in accordance with ISO 7500-1, in which the rate of increase of specimen length is uniform with time, fitted with jaws which are sufficientl
36、y wide to hold the entire width of the specimen and equipped with appropriate means to limit slippage or damage. 8.2 Clamps Compressive jaws should be used for most materials, but for materials where the use of these grips gives rise to excessive jaw breaks or slippage, capstan grips may also be use
37、d. It is essential to choose jaw faces that limit slippage of the test specimen, especially in the case of high-strength geotextiles. 9 Test procedure 9.1 Setting up the machine Adjust the distance between the jaws at the start of the test to obtain the required test specimen length 3 mm. Select the
38、 force range of the testing machine such that rupture occurs between 10 % and 90 % of full-scale force. Set the machine to the required speed of (100 5) mm/min. If capstan grips are used, the distance between the centres of the capstan grips is used as a reference. The distance between the centres o
39、f the capstans at the beginning of each test shall, as far as possible, be kept equal to 160 mm for a shear test and 100 mm for a peel test. The use of capstan grips shall be recorded in the test report. 9.2 Insertion of test specimen in the jaws Mount the test speciment (Test A or Test B type) cent
40、rally in the jaws. Take care that the specimen length is parallel to the direction of the applied force by positioning the drawn lines (see 7.2) parallel and as close as possible to the inside edges of the jaws. 9.3 Measurement of tensile properties Start the tensile machine and continue until the s
41、pecimen fails or ruptures or until a total run distance of 100 mm for the shear test and of 200 mm for the peel test is reached. Record the force-deformation plot (see Figure 5). The mode of failure shall also be recorded for each specimen (either peel or shear or break of one or two of the geosynth
42、etics). The decision to discard a test result shall be based on observation of the specimen during the test and on the inherent variability of the geosynthetic. In the absence of other criteria for rejecting jaw breaks, any rupture occurring within 5 mm of the jaws, which results in a value below 50
43、 % of the average breaking strength, shall be discarded. No other results shall be discarded, unless the test is known to be faulty. It is difficult to determine the precise reason why certain specimens break near the edge of the jaws. If a jaws break is caused by damage to the test specimen by the
44、jaws, the result should be discarded. If, however, it is merely due to randomly distributed weaknesses in the test specimen, it is a legitimate result. In some cases, it may also be caused by a concentration of stress in the area adjacent to the jaws, because they prevent the test specimen from cont
45、racting in width as the load is applied. In these cases, a break near the edge of the jaws is inevitable and should be accepted as a characteristic of the particular method of test. EN ISO 13426-2:2005 6 Special procedures are required for the testing of specimens made from specific materials (e.g.
46、glass fibre, carbon fibre) to minimize any damage that may be caused by the jaws. If a test specimen slips in the jaws, or if more than one quarter of the specimens breaks at a point within 5 mm of the edge of the jaw, then a) the jaws may be padded, b) the test specimen may be coated under the jaw
47、face area, or c) the jaw face may be modified. If any of the modifications listed above are used, the method of modification should be stated in the test report. 10 Calculations For both the shear and peel tests, the force-deformation plot of a specimen can show one of the following types of behavio
48、ur: multiple peaks (Figure 5); delamination (Figure 6); single peak (Figure 7); tensile failure (Figure 8). The force F peel or F shearfor each specimen is determined directly from the force-deformation plot. The procedure is graphically demonstrated in Figures 5 to 8. Determine the F peelor F shear
49、values for all specimens. Calculate the mean value shear F or peel F of the F peelor F shearvalues. Calculate the junction strength per unit width T peelor T shear(in kN/m): T shear= F shear /b shear(1) T peel= F peel / peel(2) where b peel , b shearare the specimen widths, in metres, for peel and shear tests. For products with discrete junctions (example stitching every 300 mm), the following equations shall be used: T shear=
