1、BSI Standards PublicationUse of k-value concept, equivalent concrete performance concept and equivalent performance of combinations conceptPD CEN/TR 16639:2014National forewordThis Published Document is the UK implementation of CEN/TR 16639:2014.The UK participation in its preparation was entrusted
2、by TechnicalCommittee B/517, Concrete, to Subcommittee B/517/1, Concrete production and testing.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions ofa contract. Users are responsib
3、le for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 83192 8ICS 91.100.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This Published Document was published under the authority of theStandards P
4、olicy and Strategy Committee on 30 April 2014.Amendments/corrigenda issued since publicationDate Text affectedPUBLISHED DOCUMENTPD CEN/TR 16639:2014TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 16639 March 2014 ICS 91.100.30 English Version Use of k-value concept, equivalent concrete
5、 performance concept and equivalent performance of combinations concept Utilisation du concept de coefficient k, concept dquivalence de performance et concept dquivalence de performance en combinaison k-Wert-Ansatz, Prinzipien des Konzepts der gleichwertigen Betonleistungsfhigkeit und Konzept der gl
6、eichwertigen Leistungsfhigkeit von Kombinationen aus Zement und Zusatzstoff This Technical Report was approved by CEN on 26 November 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 R
7、epublic, 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. EUROP
8、EAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 16639:2014 EP
9、D CEN/TR 16639:2014CEN/TR 16639:2014 (E) 2 Contents Page Foreword 3 0 Introduction 4 0.1 General 4 0.2 Task Group 5 4 0.3 k-value concept 4 0.4 ECPC and EPCC.4 1 Scope 5 2 k-value concept 6 2.1 k-values in EN 206:2013 6 2.2 Use of k-values in the member states .6 2.3 Procedure for using the k-value
10、concept 7 2.3.1 Principle of the k-value concept .7 2.3.2 Method of calculation 8 2.3.3 Example for determination of k . 10 2.3.4 Further recommendations for the application of the k-value . 12 2.3.5 Example for establishing a general concept using the k-value concept 12 2.4 Application of k-value c
11、oncept by the users . 14 2.4.1 General . 14 2.4.2 Example for concrete mix design applying the k-value concept . 14 3 Equivalent concrete performance concept (ECPC) 15 3.1 General . 15 3.2 Dutch Method 15 3.2.1 Definitions . 15 3.2.2 Procedure and criteria for assessment of durability aspects 17 3.2
12、.3 Test methods . 22 3.2.4 Quality assurance . 23 3.3 Recommendations for the application of ECPC 24 3.4 Additional information to the use of the Dutch method . 25 4 Equivalent performance of combinations concept . 26 4.1 General . 26 4.2 UK method . 27 4.3 Irish method 28 4.4 Portuguese method 29 4
13、.5 Recommendation for application of EPCC 30 4.6 Additional information the UK method . 30 4.6.1 Annexes from BS 8500-2 relating to conformity control of combinations . 30 4.6.2 How this works when specifying concrete to BS 8500 . 35 4.7 Additional information to the Irish method 39 4.8 Additional i
14、nformation to the Portuguese method 41 Annex A (informative) Replies to the k -value questionnaire of CEN/TC 104/SC 1/TG 5 . 47 A.1 General questionnaire 47 A.2 Addition to answer of Finland . 57 Bibliography . 60 PD CEN/TR 16639:2014CEN/TR 16639:2014 (E) 3 Foreword This document (CEN/TR 16639:2014)
15、 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 id
16、entifying any or all such patent rights. PD CEN/TR 16639:2014CEN/TR 16639:2014 (E) 4 0 Introduction 0.1 General This report outlines the current understanding of the use and application of three concepts used within EN 206:2013 for Type II additions to concrete. These are the k-value concept, the Eq
17、uivalent Concrete Performance Concept (ECPC) and Equivalent Performance of Combinations Concept (EPCC). Within 5.2.5 of EN 206:2013 k-values are given for fly ash and silica fume and a recommended k-value for GGBS as well as general principles for the ECPC and the EPCC concepts. It is also stated in
18、 EN 206:2013 that modifications to the rules of application of the k-value concept are permitted if suitability is established. As stated within EN 206:2013 the establishment of suitability should result from provisions valid in the place of use of the concrete. In order to further explain the three
19、 concepts and to give guidance to the regulation writers and users of these concepts, this report provides background information and an overview of these concepts and rules of application as used within Europe. 0.2 Task Group 5 CEN/TC 104/SC 1 created Task Group 5 (TG 5) “Use of Additions” and assi
20、gned them the task to update EN 206-1:2000, 5.2.5 as part of the revision of EN 206-1. Because of the publication of product standard EN 15167-1 for ground granulated blastfurnace slag (GGBS), TG 5 was also asked to include rules for GGBS. CEN/TC 104/SC 1 passed various resolutions instructing TG 5
21、that it should implement the EPCC and ECPC concepts and the existing k-value concept for use of additions at the concrete mixer. The rules for the use of type II additions in concrete according to EN 206:2013 are given in 5.2.5 “Use of additions”. For two additions, fly ash and silica fume, specific
22、 requirements for their use with k-values are given. In this prescriptive k-value concept for concrete mix design, the defined rules are on the safe side and cover all possible variations for the possible permutations of cement and addition. An alternative option is the use of ECPC and EPCC concepts
23、. Their principles are described in EN 206:2013, 5.2.5.3 and 5.2.5.4 while examples for the assessment using these concepts are given in this CEN/TR. The rules for these performance concepts should also be safe and lead to a more efficient use of additions. 0.3 k-value concept With respect to the k-
24、value concept in EN 206:2013, it was agreed that for fly ash and silica fume prescriptive k-values and cement substitution rates will be given which are proven to be on the safe side. Although the k-value concept for GGBS is included in some national regulations (see /2/) only a recommended value is
25、 given in EN 206:2013 due to limited practical experience. In national provisions, however, modifications to the rules of the k-value concept may be applied where their suitability has been established, e.g. higher k-values, increased proportions of additions, other additions (including type I), com
26、binations of additions and other cements than those normally permitted. In this report the derivation of the prescriptive k-value approach is explained. The report also describes how the k-value concept should be applied by users such as the concrete producers. 0.4 ECPC and EPCC The equivalent perfo
27、rmance concepts, ECPC and EPCC, for the use of additions may be applied where suitability has been established. In countries where ECPC and EPCC are applied, nearly always, GGBS as addition to concrete is used under these concepts. This report describes how the ECPC and EPCC are applied in some Euro
28、pean countries. PD CEN/TR 16639:2014CEN/TR 16639:2014 (E) 5 1 Scope This Technical Report provides more detailed information on the k-value concept principles of the equivalent concrete performance concept (ECPC) and the equivalent performance of combinations concept (EPCC) in accordance to EN 206:2
29、013, 5.2.5. PD CEN/TR 16639:2014CEN/TR 16639:2014 (E) 6 2 k-value concept 2.1 k-values in EN 206:2013 The k-value concept has been established for a number of years in a number of countries and was therefore implemented in EN 206-1 for fly ash and silica fume. In CEN/TC 104/SC 1 report N 278 (June 1
30、996) the background was given to the application of k-value concept with fly ash concrete 1. Later this concept was also applied for concretes containing silica fume and in some member states k-values for concretes with ground granulated blastfurnace slag (GGBS) are given in national application doc
31、uments. In EN 206:2013 prescriptive k-values are given for fly ash and silica fume and a recommended one for GGBS. These k-values allow the use of these additions in concrete throughout Europe with a restricted range of cement types within the requirements of the standard without any further verific
32、ation procedure, i.e. without further testing except for the normal quality control for the concrete. In a prescriptive concept for concrete mix designs, the defined rules shall be on the safe side and cover all possible combinations of materials and variations for the given addition. The k-value co
33、ncept is a prescriptive concept. It is based on the comparison of the durability performance (or strength as a proxy-criterion for durability where appropriate) of a reference concrete with cement “A” against a test concrete in which part of cement “A” is replaced by an addition as function of the w
34、ater/cement ratio and the addition content. With the proof of durability indirectly the proof for the exposure classes is given. The k-value concept permits type II additions to be taken into account: by replacing the term “water/cement ratio” with “water/(cement + k * addition) ratio” and; the amou
35、nt of (cement + k * addition) shall not be less than the minimum cement content required for the relevant exposure class. When part of Cement “A” is replaced by an addition, the limiting values that have to be applied are those that would apply for Cement “A”. The rules of application of the k-value
36、 concept for fly ash conforming to EN 450-1, silica fume conforming to EN 13263-1 and ground granulated blast furnace slag conforming to EN 15167-1 together with cements of type CEM I and CEM II/A conforming to EN 197-1 are given in corresponding clauses in EN 206:2013. Modifications to the rules of
37、 the k-value concept may be applied where their suitability has been established (e.g. higher k-values, increased proportions of additions, other additions (including type I), combinations of additions and other cements than permitted. 2.2 Use of k-values in the member states The use of k-values for
38、 type II additions in concrete has developed differently across the European member states over years. Within the revision work of EN 206:2013 member states experience was compiled with a series of differing enquiries. In 2007 a “Survey of National requirements used in conjunction with EN 206-1:2000
39、” was published 2. For the use of additions this enquiry was focused to the regulations for different classes of LOI for fly ash, environmental compatibility and the use of k-values, especially for fly ash and silica fume. Five countries responded on the use of k-values for GGBS. In March 2007, CEN/
40、TC 104/WG 15 presented the results of a survey on the “Use of GGBS as a type II addition in concrete to EN 206-1”. Eight countries reported on the use of GGBS and it was found that GGBS is used as type II addition under the ECPC, EPCC and the k-value principles. However, the amount used based on the
41、 k-value concept is relatively limited and this experience is confined only to some Nordic countries 3. Within the revision work of 5.2.5 “Use of additions” in EN 206:2013, TG 5 also prepared an enquiry on the use of k-values for additions 4 focusing the experience with the different additions, the
42、k-values and the determination of these k-values. In total 12 countries answered to the enquiry. Three countries do not use the PD CEN/TR 16639:2014CEN/TR 16639:2014 (E) 7 k-value concept as they are using existing performance concepts and one country does not use the k-value concept for GGBS result
43、ing in nine countries with regulations for using GGBS with the k-value concept. The answers of the enquiry can be compiled as follows: The k-value was mostly established based on results of research work and experience. The compressive strength is mostly evaluated after 28 days on concrete samples (
44、9 countries) or mortar (1 country). Where the k-value was determined the relationship between the compressive strength and water/cement-ratio of concrete samples was used. The type of cement and the maximum proportions of additions permitted vary widely in the National regulations, from the use with
45、 CEM I only to the use with all cements where the additions are also used in cement. Fly ash is used with more cement types than silica fume and GGBS using the k-value concept. k-values for fly ash vary from 0,2 to 0,8, those for silica fume from 1,0 to 2,0 and those for GGBS from 0,4 to 1,0. Where
46、k-values had been determined the durability aspects had also been taken into account. Most of the countries have experience with k-value concept for fly ash and silica fume, only a few countries use the k-value concept for GGBS. The single answers to the TG 5 enquiry are given at the end of this rep
47、ort. 2.3 Procedure for using the k-value concept 2.3.1 Principle of the k-value concept Type II additions contribute to concrete properties by various mechanisms. Their influence on concrete properties depends on the characteristics of the individual material properties, on the age of concrete, on t
48、he ambient conditions (temperature, humidity) and various other parameters. To take into account these effects in the concrete mix design, the k-value method uses the relationship between the water/cement ratio and the strength of concrete. The concept was introduced by Iain A. Smith for the first t
49、ime in 1967 for the design of fly ash concretes with fly ash amount up to 25 % 5 and has developed further on. Based on the established concept of EN 206-1 and related Eurocodes the concrete mix design is based on the 28 days strength of concrete. Consequently the standardised prescriptive k-value for a concrete addition is related to this age. Nevertheless, when a k-value has to be defined, the durability of concretes shall be considered for the relevant exposure classes. In concretes containing type II additions, the term “water/cement
