Geoscience Reference
In-Depth Information
For geotextiles there is no classification within the CE marking and so it cannot
be established that a geotextile must have, for example, a tensile strength greater than
30 kN/m for use in a hydraulic application. CE marking distinguishes various func-
tions for which a geotextile can be used. They are as follows:
reinforcement;
separation;
filtration;
drainage.
To be able to assess the extent to which a geotextile can fulfill the required
function, prescriptions are made per application area on which (characteristic)
properties of the geotextile must be made available by the manufacturer to be able
to compare geotextiles with each other and, where possible, judge their performance
in-situ. Minimum requirements are described in the application standards EN 13249
to EN 13257 and EN 13265 for geotextiles. Of importance for the application of
geotextile-encapsulated sand elements is EN 13253 “Geotextiles and geotextile -
related products - Required characteristics for use in erosion control works”.
If a geotextile is considered suitable for filtration then the “water permeability
normal to the plane”, for example, must be known. This means that only a value
measured according to the representative standard is known for the permeability, not
that it must be greater than a certain minimum value, which is dependent on in-soil
conditions. Three kinds of test have been defined:
The so-called “harmonized tests”, the results of which are used not only to deter-
mine a parameter but also to indicate whether the quality of the product is con-
sistent. The manufacturer has to indicate which quality procedure is followed to
ensure that the test results on his product remain within the spread indicated by
the manufacturer (
H
).
The tests that have to be performed in all cases. The results of the tests that are
stated for a function must be known in order to use the geotextile for that func-
tion (
A
).
The tests that are required in some cases only, such as certain chemical tests that
only have to be performed if the geotextile is expected to come into contact with
different environments (
S
).
An example of how the information is presented in a CE application standard is
shown in Table B.1. The results from the stated tests are made available upon delivery
of the geotextile to site. The CE marking (on the geotextile rolls) shows the properties
necessary to meet the relevant application standard. The advantages for the user of
geotextiles containing a CE marking are:
the manufacturer has a recognized quality control system, along with an independ-
ent verification organization examining whether there is sufficient justification to
present the values and their variation as stated by the manufacturer. According to
the European regulations geosynthetics (which include geotextiles) are a category
of products where the manufacturer can state what will be their value and their
