SIST EN 1897:2001
(Main)Geotextiles and geotextile-related products - Determination of the compressive creep properties
Geotextiles and geotextile-related products - Determination of the compressive creep properties
This standard describes methods for determining the compressive creep behaviour of geotextiles and geotextile-related products by measurement of the rate of change of thickness with respect to time.
Geotextilien und geotextilverwandte Produkte - Bestimmung des Kriechverhaltens unter Druckbeanspruchung
Diese Europäische Norm legt Index-Prüfverfahren zur Bestimmung des Verhaltens von Geotextilien und geotextilverwandten Produkten unter Druckbeanspruchung fest.
Die Messproben können entweder einer Beanspruchung durch eine Normaldruckkraft oder einer Beanspruchung durch die Kombination einer Normaldruckkraft und einer Scherkraft unterworfen werden. Produkte, die gegen Scherbeanspruchung anfällig sind, d. h. Produkte mit einer säulenartigen oder kegel- oder pyramidenförmigen Struktur der Abstandshalter, sollten nach dem Verfahren mit der kombinierten Anwendung von Normal- und Scherkräften geprüft werden (siehe Abschnitt 6), während alle anderen Produkte unter Anwendung nur einer Normalkraft geprüft werden können (siehe Abschnitt 5).
Die Prüfungen werden an trockenen oder in Wasser eingetauchten Messproben durchgeführt.
Géotextiles et produits apparentés - Détermination des propriétés de fluage en compression
Domaine d'application
La présente Norme européenne spécifie des méthodes d'essai de référence pour déterminer le comportement en compression des géotextiles et des produits apparentés aux géotextiles.
Les éprouvettes peuvent etre soumises soit a une charge de compression normale, soit a une combinaison de charge de compression normale et de charge de cisaillement. Il convient que les produits sensibles a la rupture par cisaillement, a savoir les structures en colonne ou en pointe, soient soumis aux essais avec la méthode de charge normale et la méthode de charge de cisaillement (voir article 6) ; tous les autres produits peuvent etre soumis a l'essai de charge normale uniquement (voir article 5).
Les essais sont effectués sur l'éprouvette seche ou en immersion dans l'eau.
Geotekstilije in geotekstilijam sorodni izdelki - Ugotavljanje lastnosti lezenja pri tlačenju
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 1897:2001
01-december-2001
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SIST ENV 1897:1999
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Geotextiles and geotextile-related products - Determination of the compressive creep
properties
Geotextilien und geotextilverwandte Produkte - Bestimmung des Kriechverhaltens unter
Druckbeanspruchung
Géotextiles et produits apparentés - Détermination des propriétés de fluage en
compression
Ta slovenski standard je istoveten z: EN 1897:2001
ICS:
59.080.70 Geotekstilije Geotextiles
SIST EN 1897:2001 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 1897:2001
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SIST EN 1897:2001
EUROPEAN STANDARD
EN 1897
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2001
ICS 59.080.70 Supersedes ENV 1897:1996
English version
Geotextiles and geotextile-related products - Determination of
the compressive creep properties
Géotextiles et produits apparentés - Détermination des Geotextilien und geotextilverwandte Produkte -
propriétés de fluage en compression Bestimmung des Kriechverhaltens unter
Druckbeanspruchung
This European Standard was approved by CEN on 9 June 2001.
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-date lists and bibliographical references concerning such national
standards may be obtained on application to the 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
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1897:2001 E
worldwide for CEN national Members.
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SIST EN 1897:2001
EN 1897:2001 (E)
Foreword
This European Standard has been prepared by Technical Committee CEN/TC 189
"Geosynthetics ", the secretariat of which is held by IBN.
This European Standard shall be given the status of a national standard, either by
publication of an identical text or by endorsement, at the latest by January 2002, and
conflicting national standards shall be withdrawn at the latest by January 2002.
This European Standard replaces ENV 1897:1996.
According to the CEN/CENELEC Internal Regulations, the national standards organizations
of the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
2
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SIST EN 1897:2001
EN 1897:2001 (E)
1 Scope
This European Standard specifies index test methods for determining the compressive
behaviour of geotextiles and geotextile-related products.
The test specimens can be subjected either to normal compressive loading or to a
combination of normal compressive loading and shear loading. Products which are sensitive to
shear failure, i.e. which have a columnar or cuspated structure, should be tested with both
normal and shear loads applied (see clause 6), all other products can be tested with a normal
load only (see clause 5).
The tests are carried out with the specimen dry or immersed in water.
2 Normative References
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate points in the text and
the publications are listed hereafter. For dated references, subsequent amendments to or
revisions of any of these publications apply to this European Standard only when incorporated
in it by amendment or revision. For undated references, the latest edition of the publication
referred to applies (including amendments).
EN 963 Geotextiles and geotextile-related products - Sampling and
preparation of test specimens.
EN 964-1 Geotextiles and geotextile-related products - Determination of
thickness at specified pressures - Part 1 : Single layers
ISO 554 Standard atmospheres for conditioning and/or testing – Specification.
ISO 3696 Water for analytical laboratory use - Specification and test methods
3 Terms and definitions
For the purposes of this European Standard the following terms and definitions apply.
3.1
thickness
the distance, in millimetres, between the two rigid plates in contact with the specimen at any
stage in the test (see Figures 1 and 2).
3.2
compression creep (t )
g
time dependent change in thickness of a material subjected to a constant compressive load
after the initial compression (t ) of the specimen.
o
3.3 initial thickness(t )
i
the thickness, in millimetres, of the specimen when subject to an applied normal stress of
5 kPa, when measured in accordance with EN 964-1.
3
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SIST EN 1897:2001
EN 1897:2001 (E)
3.4
compressive strain ():
the time dependent change in thickness, expressed as a percentage of the initial thickness.
3.5
initial compression (t )
o
the change in thickness which occurs immediately after the specimen is loaded; the
difference between the initial thickness and the thickness measured at 1 min (normal
loading only) or 4 min (normal and shear loading).
3.6
compressive creep collapse
sudden increase in the rate of change in thickness of a specimen subject to a constant
compressive load.
4 Test specimens
4.1 Sampling
Take specimens in accordance with EN 963.
4.2 Number and dimensions of test specimens
Cut eight specimens from the test sample for each test procedure to be followed; a new
specimen is required for each test.
The size of each specimen shall satisfy the following criteria:
- the specimen shall be square and have a minimum size of 100 mm x 100 mm (see
Figure 1);
- if the specimen has a structure in which loading is resisted at defined points or
areas, then the loading plate shall cover at least three of these points or areas in
both directions (see Figure 2);
- specimens shall be cut with the sides parallel to the length and width of the sample.
4.3 Conditioning
The test specimens shall be conditioned and the tests conducted in the standard
atmosphere for testing, i.e. at a relative humidity of (65 ± 5) % and a temperature of
(20±2) °C (according to ISO 554). The test specimens can be considered to have been
conditioned when the change in mass of the test specimen in successive weighings made at
intervals of not less than 2 h does not exceed 0,25 % of the mass of the test specimen.
The test shall be carried out with the specimen immersed in water, where any part of the
geotextile or geotextile-related product contains a hydrophilic polymer. Where the test is to
be carried out with the specimen immersed in water, the specimen shall be soaked in water
for 24 h prior to the test. The water shall be maintained at a temperature of (20±2) °C. The
water to be used shall be deionised water according to ISO 3696.
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SIST EN 1897:2001
EN 1897:2001 (E)
5 Normal compressive load method
5.1 Principle
The geotextile specimen is placed on the fixed base of a compression machine with an
upper loading plate, the vertical compressive load is applied and the change in thickness is
recorded with time. The vertical compressive load is applied to the specimen for a period of
1000 h with greater or lesser times by agreement.
5.2 Apparatus
5.2.1 Compression testing machine.
A compression testing machine with a vertical travel greater than the initial thickness of the
specimen, shall be used. It shall be capable of sustaining the applied stress to within 1%
accuracy for the duration of the test.
The compressive stress may be applied mechanically, pneumatically, or hydraulically.
Where hydraulic or pneumatic loading systems are used, the stress applied shall be
constant for the duration of the test.The loading device, however, shall be capable of
applying the full stress in one controlled step, i.e. without significant impact, within a period
of 60 s.
Some systems may use dead weights to apply the stress. In systems using dead weights
the loading system shall be fully supported while being assembled such that no load is
applied to the specimen until the support is smoothly released (see Figure 3).
The compression testing apparatus shall include a fixed base plate and a parallel moveable
top plate, both with a flat steel surface. The dimensions of the top plate shall be at least
equal to those of the specimen and its thickness shall be such that it will result in a normal
pressure of not greater than 5 kPa to the specimen (see Figure 2).
5.2.2 Specimen container
If the test is to be carried out with the specimen immersed in water, a container to keep the
specimen immersed and at a constant temperature shall be used. The water level in the
container shall cover the specimen but the height of water above the specimen shall not
exceed 25 mm.
5.2.3 Thickness measurement
A means of measuring the mean thickness of the specimen to a precision of 0,02 mm shall
be used. Unless measurements are taken at the centre of the specimen, measurements
shall be taken at a minimum of three equally spaced points. If three or more measurement
points are used, the thickness is the mean of the values recorded.
5.2.4
Timer
Time shall be recorded throughout the test period.
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SIST EN 1897:2001
EN 1897:2001 (E)
5.3 Test procedure
Measure the initial thickness of the sample in accordance with EN 964-1, using a normal
stress of 5 kPa.
Ensure that the specimen is placed symmetrically on the base plate and covered with the
top plate.
Apply the load needed to give the required normal compressive stress in less than 60 s.
The normal stresses to be applied shall be as follows:
20 kPa, 50 kPa, 100 kPa and 200 kPa
A new specimen shall be used for each test, two specimens shall be tested at each of the
specified stresses.
Record the thickness of the specimen at the following time intervals after the application of
the test stress:
1 min, 2 min, 4 min, 15 min, 30 min, 60 min,
2 h, 4 h, 8 h, 24 h,
and 2 days, 4 days, 7 days, 14 days, 28 days, 42 days.
NOTE The test may be terminated when the recorded thickness of the specimen is
less than 10% of the nominal thickness.
Repeat the test on the other specimens. Carry out calculations as defined in 5.4 .
5.4. Calculations
Applied normal stress is calculated as follows:-
= N/A
where = normal stress in kilopascals (kPa);
N = applied load in kilonewtons (kN);
2
A = area of specimen in square metres (m ).
The area of a cuspated or columnar sample shall be calculated by counting the number of
contact points in a 1,0 m width and length to determine the number of contact points in
2
1,0 m . The area of specimen is then calculated as :
Number of contactpoint s in the specimen
A
Number of contactsin one square
...
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