CEN/TR 16563:2013

SLOVENSKI STANDARD
01-december-2013
3RVWRSNRYQDQDþHOD]DXJRWDYOMDQMHWUDMQRVWL
Principles of the equivalent durability procedure
Verfahrensgrundsätze zum Nachweis gleichwertiger Dauerhaftigkeit
Principes de la procédure de durabilité équivalente
Ta slovenski standard je istoveten z: CEN/TR 16563:2013
ICS:
91.100.30 Beton in betonski izdelki Concrete and concrete
products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL REPORT
CEN/TR 16563
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
August 2013
ICS 91.100.30
English Version
Principles of the equivalent durability procedure
Principes de la procédure de durabilité équivalente Verfahrensgrundsätze zum Nachweis gleichwertiger
Dauerhaftigkeit
This Technical Report was approved by CEN on 22 June 2013. It has been drawn up by the Technical Committee CEN/TC 104.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 16563:2013: E
worldwide for CEN national Members.

Contents Page
Foreword .3
Introduction .4
1 Scope .5
2 Normative references .5
3 Terms and definitions .6
4 Principle .7
5 Selection of test methods .8
6 Determination of the reference value .9
7 Determination of equivalent durability-related test performance . 11
8 Production control . 13
9 Evaluation and declaration of equivalent durability-related test performance . 14
10 Interface with users . 14
Annex A (informative) Finland —Testing of freeze-thaw resistance of a candidate concrete . 16
Annex B (informative) Germany . 19
Annex C (informative) Italy . 28
Annex D (informative) The Netherlands . 29
Annex E (informative) Norway . 31
Annex F (normative) The system used in Portugal and defined in their national annex to EN 206-1 . 32
Annex G (informative) Spain . 34
Annex H (informative)  United Kingdom . 36
Bibliography . 37

Foreword
This document (CEN/TR 16563:2013) has been prepared by Technical Committee CEN/TC 104 “Concrete
and related products”, the secretariat of which is held by DIN.
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 any or all such patent rights.
Introduction
(1) The Equivalent Durability Procedure (EDP) is a scheme that builds on the traditional method of ensuring
durable concrete by specifying established limiting values in terms of maximum w/c ratio, minimum cement
content etc. Essentially, a reference value is determined and a candidate concrete can be confirmed as being
of equivalent performance where testing and other appropriate assessments are made to demonstrate
equivalent performance with this reference value or reference concrete. The reference value is determined
based on concretes that satisfy fully the limiting value specification valid in the place of use and are
representative of concretes that are successfully used in the local environment as providing a satisfactory
service-life. To be considered a viable alternative, the proposed candidate concrete need to have a test
performance that equals, or is better than, the reference value when tested by the same method and at the
same age as used to establish the reference performance. Such a comparison leads to equivalent
performance in the test at the age of testing. As the rate of improvement in resistance is not constant between
concretes, the reference value will be appropriate for the constituents used in the candidate concrete.
(2) No relatively short-term laboratory test will give a precise quantitative indication of real performance of in-
situ concrete. One reason for this is that concrete will continue to gain strength and resistance to the
permeation of aggressive species in most natural environments, e.g. concrete will increase its resistance to
the permeation of chloride ions with time, albeit at an ever decreasing rate. Such changes in performance
over time, collectively called ‘ageing effects’, need to be taken into account when determining if the candidate
concrete will provides an equivalent durability over the service-life.
NOTE With respect to durability, the changes can be positive or negative. For example, reaction with seawater may
result in a surface layer that increasingly inhibits the penetration of chloride ions and hence improve durability. On the
other hand, carbonation of concrete may release chlorides ions that were previously bound into the hydrate structure and,
as these are then free to migrate towards any reinforcement, the durability may be reduced.
(3) Some CEN members have established national EDP type procedures which provide results that are likely
to be reasonably indicative of in-situ performance or procedures whereby equivalent durability may be safely
assumed for defined sets of materials. See Annex A to Annex H for some examples.
(4) This Technical Report provides guidance to National Standards Bodies who want to establish an EDP in
their national provisions to EN 206.

1 Scope
This Technical Report sets out the principles of the equivalent durability procedure. It provides guidance on
the selection of the reference value, production control, evaluation of conformity and the exchange of
information between the parties.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
EN 196-1, Methods of testing cement — Part 1: Determination of strength
EN 197-1, Cement — Part 1: Composition, specifications and conformity criteria for common cements
EN 206-1, Concrete — Part 1: Specification, performance, production and conformity
EN 450-1, Fly ash for concrete — Part 1: Definition, specifications and conformity criteria
EN 480-11, Admixtures for concrete, mortar and grout — Test methods — Part 11: Determination of air void
characteristics in hardened concrete
EN 933-9, Tests for the geometrical properties of aggregates — Part 9: Assessment of fines — Methylene
blue test
EN 1992-1-1, Eurocode 2 — Design of concrete structures — Part 1-1: General rules, and rules for buildings
EN 12350-1, Testing fresh concrete — Part 1: Sampling
EN 12390-2, Testing hardened concrete — Part 2: Making and curing specimens for strength tests
EN 12390-3, Testing hardened concrete — Part 3: Compressive strength of test specimens
EN 12390-8, Testing hardened concrete — Part 8: Depth of penetration of water under pressure
CEN/TS 12390-9, Testing hardened concrete — Part 9: Freeze-thaw resistance  Scaling
CEN/TS 12390-10, Testing hardened concrete — Part 10: Determination of the relative carbonation
resistance of concrete
CEN/TS 12390-11, Testing hardened concrete — Part 11: Determination of the chloride resistance of
concrete, unidirectional diffusion
EN 12620, Aggregates for concrete
EN 13263-1, Silica fume for concrete — Part 1: Definitions, requirements and conformity criteria
EN 13295, Products and systems for the protection and repair of concrete structures — Test methods —
Determination of resistance to carbonation
EN 13369, Common rules for precast concrete products
EN 13396, Products and systems for the protection and repair of concrete structures — Test methods —
Measurement of chloride ion ingress
EN 13670, Execution of concrete structures
EN 14216, Cement — Composition, specifications and conformity criteria for very low heat special cements
EN 15167-1, Ground granulated blast furnace slag for use in concrete, mortar and grout — Part 1: Definitions,
specifications and conformity criteria
CEN/TR 15177, Testing the freeze-thaw resistance of concrete — Internal structural damage
ISO 5725-6, Accuracy (trueness and precision) of measurement methods and results — Part 6: Use in
practice of accuracy values
ISO 16204, Durability — Service life design of concrete structures
BS 7979, Specification for limestone fines for use with Portland cement
BS 8500-1, Concrete — Complementary British Standard to BS EN 206-1 — Part 1: Method of specifying and
guidance for the specifier
BS 8500-2, Concrete — Complementary British Standard to BS EN 206-1 — Part 2: Specification for
constituent materials and concrete
DIN 1045-2, Concrete, reinforced and prestressed concrete structures — Part 2: Concrete — Specification,
properties, production and conformity — Application rules for DIN EN 206-1
LNEC E 391, Concrete. Determination of carbonation resistance (In Portuguese)
LNEC E 392, Concrete. Determination of the permeability to oxygen (In Portuguese)
LNEC E 393, Concrete. Determination of the absorption of water through capillarity (In Portuguese)
LNEC E 463, Concrete. Determination of diffusion coefficient of chlorides from non-steady state migration test
(In Portuguese)
NEN 8005, NEN, Nederlandse invulling van NEN-EN 206-1: Beton — Deel 1: Specificatie, eigenschappen,
vervaardiging en conformiteit (Dutch supplement to NEN-EN 206-1)
NT BUILD 492, Concrete, mortar and cement-based repair materials: chloride migration coefficient from non-
steady-state migration experiments
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
ageing effects
changes in a concrete resistance to aggressive species as the result of the progression of the hydration
together with the time evolution of cement phase microstructure, its interaction with the penetration species
and, in certain cases, of concrete surface changes due to its direct interaction with the external environment
Note 1 to entry: Example for interaction with the penetration species is: chloride binding.
Note 2 to entry: Example for direct interaction with external environment is: a skin effect when concrete is exposed to
seawater.
3.2
candidate concrete
concrete comprising a closely defined set of constituents under investigation to determine the mix proportions
that are likely to provide a durability performance equal to or greater than a reference value or reference
concrete for the selected exposure class
3.3
equivalent durability – related test performance
procedure based on testing, by which a candidate concrete is shown to have equal or better performance than
a reference value - when checked for the performance criteria linked to a selected exposure class
Note 1 to entry: The process includes the definition of the performance value, testing the candidate concrete with a
performance test at a specified age, and comparing it with the appropriate reference value of performance or the
performance of the reference concrete at the same age.
3.4
reference concrete
concrete where all the constituents and mix proportions are prescribed, conforming to the EN 206 provisions
valid in the place of use and representative of the national/local experience in the defined exposure class.
3.5
reference value
value that the candidate concrete has to achieve or be better than and which is determined from either:
a) a previously established value where this has been established from any combination of testing or
service-life modelling;
b) tests on the reference concrete;
c) a value selected from the range of values resulting from testing concretes that conform to the provisions
valid in the place of use and is representative of the national/local experience in the defined exposure
class
4 Principle
(1) The equivalent durability procedure (EDP) is a scheme for establishing conformity to EN 206 of concrete
compositions that deviate from the limiting value criteria valid in the place of use. Durability testing to meet
defined criteria is undertaken and this leads to a limiting value specification that is valid only for the
constituents used in the candidate concrete. This procedure only applies to concrete compositions that
comprise constituents (natural, manufactured or recycled) covered by European technical specifications
referred to in EN 206 or provisions valid in the place of use.
(2) The procedure is applicable to any exposure class, but in practice it is limited to exposure classes where
there are agreed standardized test methods (see 5.2). The application of the EDP is not appropriate for the X0
exposure class, as there are no environmental conditions that are aggressive to concrete or reinforcement.
(3) The EDP is to determine the equivalence of a candidate concrete used with the same minimum cover in
the same exposure classes and intended working life as those appropriate for the reference value.
(4) The EDP includes at least three parts:
 Part 1: The setting of a reference value or the prescription of a reference concrete from which a reference
value can be determined;
 Part 2: Initial testing and assessment of the candidate concrete to establish specific limiting values;
 Part 3: Continuous production control and conformity assessment to the determined limiting values.
(5) Part 1 requires for each exposure class, a reference value or a reference concrete to be selected.
(6) The Part 2 always has Stage 1 and in some cases, also a Stage 2.

Stage 1
(7) Candidate concretes are tested and compared with the reference value/concrete based on the same test
methods at the same ages. Measurement uncertainty has to be taken into account. Equivalent durability at the
age of testing is achieved when the candidate concrete has a measured value equal to or less than, i.e. better
performance than, the reference value or the measured value of the appropriate reference concrete after
taking account of measurement uncertainty.
NOTE With the carbonation test, chloride diffusion test and the freeze-thaw test, the lower the measured value the
better is the performance.
Stage 2
(8) Assessing the relative performance of a concrete at a young age may not adequately reflect relative
performance over the full life of the structure due to ageing effects. If the reference value or reference
concrete has a similar cement/addition type to the candidate concrete, Stage 2 is satisfied and the concrete
may be assumed to provide a similar durability over the life cycle. In other cases further action is required to
show a similar performance over the life cycle before the claim of an equivalent durability performance may be
made (see 7.1.3).
(9) The EDP leads to a set of limiting values that are specific to the constituents used in the initial testing.
(10) Part 3 of the procedure involves demonstrating conformity to these limiting values plus some form of
check that the constituents have not changed significantly is used to establish conformity of the production
concrete.
(11) To generate confidence in the system, it is strongly recommended that the initial testing and periodic re-
validation are undertaken by a party that is independent of the concrete producer and that testing is
undertaken by laboratories that are accredited, or approved on a national basis, for the test procedure.
5 Selection of test methods
5.1 Requirements for a test method
The test method is required to:
 be relevant to the deterioration mechanism for which performance is being compared;
 have an established and documented relationship with performance in practice in the defined exposure
class;
 be of a known and adequate precision;
 be sensitive to variations in concrete composition and mix proportions.
5.2 Guidance on the selection of test methods
(1) Where test procedures valid in the place of use are applied for the assessment of new constituents and
concretes it is appropriate to use such tests for the equivalent durability procedure. The test method applied
should have known reproducibility and repeatability standard deviations. Most European performance-related
durability test methods for concrete that are published have the status of Technical Specifications, as the test
precision had not been established. When precision data are established, the tests will be upgraded to full
European standards. Any national test method should be used in parallel with the European test procedure,
so that experience with the European tests is gained and in the longer term Europe is able to adopt common
test procedures.
(2) The performance-related test methods for concrete listed in Table 1 have been standardized and
published at the European level.
(3) Some, but not all, test methods define the age of concrete at the start of the test. The age of the concrete
at the start of the test will have an influence on the test result and it should not be presumed that a suite of
concretes tested at one age will have the same ranking when tested at a different age.
Table 1 — Performance-related test methods that are, or are being,
a
standardized at the European level
CEN/TS 12390-9 Testing hardened concrete — Part 9: Freeze-thaw resistance — Scaling
CEN/TS 12390-10 Testing hardened concrete — Part 10: Determination of the relative
carbonation resistance of concrete
CEN/TS 12390-11 Testing hardened concrete — Part 11: Determination of the chloride
resistance of concrete, unidirectional diffusion
CEN/TR 15177 Testing the freeze-thaw resistance of concrete — Internal structural
damage
a
There are no exposure classes in EN 206 for abrasion, but they exist in other European and national standards
and there are associated test methods.

6 Determination of the reference value
6.1 Requirements for a reference value
(1) Reference values may be established by:
 Selecting reference values from previously established values where these values have been determined
from any combination of testing or service-life modelling. One approach is testing a range of concretes
that fully satisfy the provisions valid in the place of use and are representative of national/local experience
and then selecting one or more representative values. If more than one representative values are
selected, each value should be associated with a particular type or types of cement or cement: addition
ratio.
 Defining reference concretes and then testing them to determine reference values. The candidate
concrete is then assessed using the same test methods as used to establish the reference values at the
same test ages.
(2) Much of what is written in this Technical Report would also apply to a reference value determined from
service-life design. However, for example, the diffusion coefficient required for the structure needs to be
converted into a value from test specimens tested by a specified method at a specified age. A minimum
requirement for ageing due to hydration would also have to be specified and how it is to be assessed, or the
cement/addition type(s) permitted in the candidate concrete defined.
(3) When setting a reference value, it is simpler to take into account measurement uncertainty and require the
measured value of the candidate concrete to achieve or be better than the reference performance, i.e. the
numerical values are directly compared. If such an approach is followed, the minimum number of test samples
for the candidate concrete will have to be specified as the uncertainty of measurement depends upon the
number of test results.
(4) Where reference values are being specified, the following information has to be provided:
 the relevant exposure class;
 the limit value of the reference performance;
 the cement/addition type(s) and ratio associated with the reference value;
 the test method to be used on the candidate concrete;
 the age of testing of the candidate concrete, if not defined in the test standard;
 whether the limit value includes or does not include an allowance for measurement uncertainty;
 if measurement uncertainty is included, the minimum number of tests on the candidate concrete.
6.2 Requirements for a reference concrete
(1) A reference concrete is a prescribed concrete that satisfies all of the following conditions:
 it is a concrete conforming to EN 206 and conforming to the provisions valid in the place of use for the
defined exposure class;
 its constituents meet the requirements of EN 206 and/or the provisions valid in the place of use for the
defined exposure class;
 it is a concrete representative of the national/local experience in the defined exposure class.
Where compressive strength is part of the durability provisions valid in the place of use, the proportions of the
reference concrete should be at least those needed to achieve the average strength of (f + 1,64σ), where f
ck ck
is the characteristic compressive strength of the concrete and σ is the estimate of the standard deviation of
the population.
(2) To ensure a consistent concrete, the reference concrete needs to be fully prescribed and in addition to the
specification requirements given in EN 206, this shall include the prescription of:
 type, source and content of the cement/addition;
 cement strength class;
 aggregate types and sources (e.g. Thames/Seine/Rhine/Tiber/Tagus Valley gravel);
 grading, shape and content of aggregates;
 admixture type, source and content.
(3) Due to potential differences in performance between different sources of the same type of cement,
addition, aggregate or admixture the source of each constituent is an essential part of the prescription.
(4) A different reference concrete(s) should be selected for each of the XC, XD, XF and XS exposure sub-
classes, e.g. XD1, XD2 and XD3, based on what is representative from those in current use. ‘Representative’
does not mean just conforming to the specified limiting values, e.g. the specified maximum w/c ratio, but a
concrete that has a history of satisfactory use in practice. Limiting value specifications usually permit a range
of constituent materials and when they are used at the same limiting values will generally not give a consistent
performance, just a range of performances that are all deemed to satisfy. The reference concrete may be
selected from the range of available representative concretes, but where the information is available it is
recommended to select one that is in the mid-range of performance. For example it is known that at a given
w/c ratio, CEM I concretes give the lower carbonation depths and cements with high levels of non-clinker
materials give high levels of carbonation. Consequently, a CEMII/B concrete, where the clinker level is in the
mid range at 65 % to 79 % clinker, would give a performance in the mid-range and may be considered an
appropriate choice of reference concrete. Alternatively, and to avoid the complications of a Stage 2
assessment, a range of reference concretes based on different cement/addition types are specified. The
candidate concrete is tested against the reference concrete with the same or similar cement type, as in the
Dutch system, see Annex D.
(5) The concept of ‘representativeness’ applies also to the constituent materials used to produce the concrete.
(6) Care should be taken to ensure a representative concrete is selected as the reference concrete. It may be
interpreted that a concrete at the limiting values would represent less than 5 % of concrete exposed to the
environment. From this starting point it may be incorrectly assumed that a concrete at the limits of
acceptability ((maximum w/c ratio + 0,02), (minimum cement content – 10 kg) and a compressive strength
– 4)) will produce a concrete that represents the
from either structural or durability requirements of (f
ck
established good performance. In reality the established good performance is based on concrete at the target
values with their normal distributions of performance. A more robust approach is to set a reference concrete
that achieves a strength of (f + 8) and a w/c ratio of the (maximum w/c ratio – 0,02) as this concrete will be
ck
representative of concrete of established suitability. Setting the reference concrete on this approach means
that normal variations in the production concrete will not reduce the durability of the production concrete below
an acceptable level.
(7) The reference concrete should have at least the minimum cement content required by the provisions valid
in the place of use that relate to EN 206 or the European precast product standard (EN 13369). In some
cases, the prescribed (target) cement content will be higher than the minimum value as more cement will be
needed to satisfy the maximum w/c ratio requirement or the w/c ratio used to achieve the strength of the
representative reference concrete.
(8) The majority of concrete produced in Europe contains at least one admixture. To reflect practice, it is
suggested that the specification for the reference concrete includes an appropriate admixture. Where the local
provisions require air entrainment for freeze-thaw resistance (XF exposure classes), the specification of the
reference concrete needs to include a specific source of air-entraining admixture and a target air content with
an appropriate tolerance.
(9) Due to the difficulties of specifying a reference concrete that will give a consistent performance, it is
strongly recommended that testing of the reference (and candidate) concretes is undertaken under the same
accredited or approved laboratory.
7 Determination of equivalent durability-related test performance
7.1 Requirements for determining the equivalent durability-related test performance
7.1.1 General
(1) Equivalent durability-related test performance is established by initial testing and it should be undertaken
by a Body that is independent of the concrete producer. This initial testing comprising Stage 1 and Stage 2 is
used to determine the mix proportions for production. The production conforming to the procedures described
in Clause 9 is taken as proof that the concrete achieves the determined limiting values and by implication an
equivalent durability performance.
NOTE Production control is used to ensure the consistency of this established performance.
(2) If in the initial testing for the selected exposure class, a candidate concrete gives results, including the
margin to take account of the uncertainties in the assessment, equivalent to, or better than, those of the
specified reference concrete or reference performance when submitted to one or more test methods that are
specified by the competent Body, e.g. a National Standards Body, the candidate concrete is deemed to have
an equivalent durability-related test performance. This initial testing is required to take account of test
precision but not potential variability of constituent materials; changes in constituent materials are taken into
account during the production control.
(3) For example, an assessment of equivalent test performance might require at least three test results each
for the reference and candidate concretes. This may, for example, be at least three results from three batches
for a single candidate concrete or at least one test result from three different mixes all made with the same set
of constituents. One of the mixes would be designed to give the required performance, one mix a better
performance and the other mix a lower performance. The mix proportions that give the equivalent test
performance may then be interpolated from the three measured values. The equivalent test performance and
the associated mix proportions should not be determined by extrapolation beyond the range of the test values.
(4) The initial testing shall lead to the identification of:
 the sources and types of all constituents (it may also include sources and types of constituents that are
demonstrably similar);
 maximum w/c ratio;
 minimum cement content;
 addition: cement ratio, where additions are used;
 minimum fines content (all particles <125μm);
NOTE For durability purposes, i.e. the achievement of a closed structure, fines are defined as all particles lower than
125 µm. ’Fines’ comprises the sum of the cement, addition, filler and the fractions of the aggregates less < 125µm in size.
 reference strength;
 if specified, the reference value for any other test procedure;
 limiting mix proportions for production.
(5) The reference strength is the compressive strength of the concrete (cylinder or cube depending upon what
measure of strength is used in production control) associated with the durability test performance of the
concrete. Changes from this value are used in the production control as an indicator of changes in the
performance of the constituents or the functioning of the plant, which could lead to an adverse change in
durability.
7.1.2 Stage 1 assessment
(1) There are various methods for dealing with the uncertainty of measurement including:
 using the known test precision, see ISO 5725-6;
 other statistical methods such as the t-test;
 applying a safe margin.
7.1.3 Stage 2 assessment
(1) The objective of the Stage 2 assessment is to evaluate the durability performances of a candidate concrete
that does not have the same rate of performance development as the reference concrete.
NOTE 1 If the cement type or (cement + addition type) is the same or similar for the reference and candidate concrete,
no Stage 2 assessment is required.
NOTE 2 At the European level quantifiable provisions for a Stage 2 assessment cannot be given at this stage of the
knowledge.
NOTE 3 For chloride resistance, one approach would be to test at two ages with the second age being at least one
year after casting. For carbonation resistance one approach is to use the CEN/TS 12390-10 test at various ages up to 12
n
months or more and calculate ‘k’ and ‘n’ in the formula carbonation depth = k (time) .
(2) If the ageing factors of the reference and candidate concretes are known, modelling may be used to
determine the equivalent durability; guidance is given in ISO 16204.
7.2 Conformity of requirements related to exposure classes
Conformity is based on conformity to EN 206 for:
 the limiting mix proportions for production determined by the initial testing (see 8.1);
 any other requirements placed on the production control, e.g. changes from the reference strength;
 other specified properties (e.g. compressive strength class, consistence).
7.3 Periodic validation or period of validity
(1) For short duration projects and where the concrete supply is shown to be consistent and of a high standard
then a re-validation of performance should not be necessary. Under other conditions, or where the client
deems it appropriate, a periodic re-validation of performance may be specified. The conditions for periodic re-
validation should be established by the appropriate national body, e.g. National Standards Body.
(2) If a re-validation leads to new limiting values, these apply to the new production. The conformity of the
concrete previously produced is not affected by any re-validation.
(3) An alternative approach and the one used for most technical approvals, is to put a time limit on the period
of validity of the determined mix proportions. With technical approvals, this is typically in the range of three to
five years.
7.4 Application at a national level
Application of this procedure at the national level requires a national application document (NAD) to define:
 for each exposure class, the reference concrete(s) or reference performance(s);
 for each exposure class, the appropriate test method or methods;
 the procedure for a Stage 2 assessment, where required;
 the minimum number of test results;
 calculation method or margin required for assessing equivalent test performance;
 conformity criteria for any test on the production that does not have criteria defined in EN 206;
 the period of validity for the determined limiting values or the maximum period between validations of
performance;
 where appropriate, a statement of the form:
The reference concrete/performance is selected to provide at least an average performance of those
concretes currently accepted under the limiting value criteria. As EDP system is conservative, such an
approach shall not be used to reject concretes that satisfy the current limiting value specification.
8 Production control
(1) The initial testing of the candidate concrete to confirm performance leads to a designed concrete with a
minimum cement content, minimum addition content where used, a fixed ratio of cement to addition and a
maximum water/(cement + addition) ratio and the reference strength for the specific set of constituents.
(2) It is recommended that the production control contains a check on whether the constituents are performing
in the same way.
(3) As designed concretes require routine testing of strength, changes in compressive strength should be
used as an indicator of change in the performance of the constituent materials/functioning of the plant.
(4) During initial testing, a reference compressive strength is determined and used to compare with
subsequent results to help detect changes in the performance of the constituents. Any change in compressive
strength should be investigated to determine the cause and whether it has a significant negative impact on
durability.
NOTE Any changes to the cement plus addition content cannot change the cement: addition ratio.
If it can be shown and it is documented that the reduction in strength is due to changes in the cement strength
or functioning of the concrete plant that has been corrected, the concrete shall be regarded as still providing
the equivalent durability test performance and the w/c ratio need not be decreased except in the case where
the specified compressive strength class is no longer being achieved.
(5) The produced concrete is required to conform to the requirements in EN 206-1 for designed concrete, e.g.
batching tolerances and tolerances on consistence, and in addition, the sources and types of constituents
shall not be changed until they have been proven by testing to be demonstrably similar.
(6) Durability-related performance tests may also be used to assess changes in the production by comparing
the performance with the reference performance determined during the initial testing.
9 Evaluation and declaration of equivalent durability-related test performance
(1) All the results and analysis of the initial testing are to be recorded. Where the testing and analysis are not
undertaken by a body that is independent of the concrete producer the records should be audited by the
producer’s certification body, or if this is not possible the audit should be carried by the second party. Testing
should be undertaken by a laboratory accredited, or approved on a national basis, for the test procedure.
(2) The test report should include:
 the type and source of constituent materials used in the investigation;
 the properties of the constituent materials;
 the test results and analysis showing the relationship between test performance and mix proportions
including the compressive strength and consistence;
 a statement of the mix proportions that give or exceed the equivalent performance;
 any observations about the likely performance in practice of the candidate concrete, e.g. over-cohesive.
(3) Before use, the producer is required to consider any observations about the likely performance and
document their actions. In the producer’s quality manual there should be a formal procedure for checking and
accepting the limiting values determined from initial testing.
(4) The assessment and verification of the constancy of production requires documentation of the sources and
types of constituent materials and a confirmation that these have been covered by the initial testing. In
addition the evaluation of conformity includes checking that the batched quantities meet the target values
within the EN 206 tolerances on batching. It should be noted that with modern auto-graphic records batch
weights may be verified for every load. Where durability-related tests are part of the assessment and
verification of the constancy of production, the results of these tests have to be documented together with the
verification of whether the constancy of production has been achieved.
10 Interface with users
(1) In the exchange of information between the producer and user prior to supply, the producer shall inform
the user that they intend satisfying the defined exposure classes using the EDP defined in the provisions valid
in the place of use.
(2) The user should check with the client’s representative, if any, that they accept durability requirements
being satisfied by an EDP procedure. In particular, the user may wish to confirm with the client’s
representative:
a) the reference value or reference concrete;
b) any limitation on types and sources of materials for the candidate concrete;
c) reference strength;
NOTE This is a target strength and not a characteristic strength.
d) assumptions made with respect to any stage 2 assessment;
e) the calculation method or margin used to assess equivalence;
f) where required time limit or frequency of any periodic re-validation.
(3) As with any offer, the user is free to accept or reject the offer.
(4) If the user as part of the concrete specification wants the performance of the concrete to be determined
and supplied under the EDP, they should allow sufficient time for the testing to be completed prior to supply.
(5) In accordance with EN 206 the producer is responsible for the declarations on the delivery ticket and this
does not change when the EDP is used to satisfy the specified exposure classes.
Annex A
(informative)
Finland —Testing of freeze-thaw resistance of a candidate concrete
A.1 Exposure classes XF1 and XF3
In exposure classes XF1 and XF3 the freeze-thaw attack takes place in the absence of de-icing salt and the
failure mechanism is internal structure damage, see example in Figure A.1. In this case, cracks develop inside
concrete which may not cause primarily scaling. In such a case, the suitable test method is CEN/TR 15177.
This test indicates the development of cracks inside concrete by measuring reduction of the dynamic modulus
of elasticity.
The ageing of the concrete does not change the freeze-thaw resistance of the concrete. Therefore, there is no
need to take into account the ageing when comparing the freeze-thaw resistance of the candidate concrete
with reference concrete.
The concrete sample is impregnated by resin and the fluorescence is visible in UV-light.
Figure A.1 — Cracks caused by freeze-thaw damage in balcony slab
Therefore, equivalent durability in terms of ‘Internal structural damage’ may be assessed by not having a
greater reduction in the dynamic modulus when tested by the procedure described in CEN/TR 15177.
A.2 Exposure classes XF2 and XF4
In exposure classes XF2 and XF4 frost-thaw attack takes place in the presence of de-icing salts. In that case
the suitable test method is CEN/TS 12390-9. The test is made with de-icing salt and the failure is seen as
scaling on the surface of the sample, see example in Figure A.2.
The effect of the ageing of the test result depends on the composition of the binder used in concrete. The
ageing effect is expressed by the formula:
( )
k = 1− 0,020 × sf + 0,008 × bfs + 0,004 × fa
binder
where
sf is the quantity of silica fume (% of binder)
bfs is the quantity of blast furnace slag (% of binder)
fa is the quantity of fly ash (% of binder)
Portland cement, CEMI, is regarded as not changing its resistance with time. When comparing the scaling of
the candidate concrete with the scaling of the reference concrete, the influence of the ageing of the concrete
on freeze-thaw resistance has to be taken into account:
m m
ref cand
=
k k
binder,ref binder,cand
Where
...