DIN EN 14651-2007 Test method for metallic fibre concrete - Measuring the flexural tensile strength (limit or proportionality (LOP) residual) (includes Amendment A1 2007) English v.pdf

1、December 2007DEUTSCHE NORM English price group 10No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 91.100.30!$K%6“140021

2、9www.din.deDDIN EN 14651SupersedesDIN EN 14651:2005-09www.beuth.deDocument comprises 19 pagesTest method for metallic fibre concrete Measuring the flexural tensile strength (limit of proportionality (LOP), residual) (includes Amendment A1:2007) English version of DIN EN 14651:2007-12 Prfverfahren fr

3、 Beton mit metallischen Fasern Bestimmung der Biegezugfestigkeit (Proportionalittsgrenze, residuelle Biegezugfestigkeit) (enthlt nderung A1:2007) Englische Fassung DIN EN 14651:2007-12 DIN EN 14651:2007-12 2 National foreword This standard has been prepared by Technical Committee CEN/TC 229 “Precast

4、 concrete products” (Secretariat: AFNOR, France). The responsible German body involved in its preparation was the Normenausschuss Bauwesen (Building and Civil Engineering Standards Committee), Technical Committee NA 005-07-08 AA Betonfertigteile (SpA CEN/TC 229). Amendments This standard differs fro

5、m DIN EN 14651:2005-09 as follows: a) Clause 10 “Test report” has been amended. Previous editions DIN EN 14651: 2005-09 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 14651:2005+A1 September 2007 ICS 91.100.30 Supersedes EN 14651:2005 English Version Test method for metallic fibre concrete - M

6、easuring the flexural tensile strength (limit of proportionality (LOP), residual) Mthode dessai du bton de fibres mtalliques - Mesurage de la rsistance la traction par flexion (limite de proportionnalit (LOP), rsistance rsiduelle) Prfverfahren fr Beton mit metallischen Fasern - Bestimmung der Biegez

7、ugfestigkeit (Proportionalittsgrenze, residuelle Biegezugfestigkeit) This European Standard was approved by CEN on 3 April 2005 and includes Amendment 1 approved by CEN on 16 August 2007. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giv

8、ing 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 CEN Management Centre or to any CEN member. This European Standard exists in three official ve

9、rsions (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 CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgi

10、um, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR

11、STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14651:2005+A1:2007: EEN 14651:2005+A1:2007 (E

12、) 2 Contents Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Symbols and abbreviated terms 5 4.1 Symbols 5 4.2 Abbreviations.5 5 Principle6 6 Apparatus .6 7 Test specimens7 7.1 Shape and size of test specimens .7 7.2 Manufacture and curing of test specimens 7 7.3 Notching o

13、f test specimens7 8 Testing procedure8 8.1 Preparation and positioning of test specimens .8 8.2 Bending test .10 9 Expression of results 11 9.1 Equivalence between CMOD and deflection.11 9.2 Limit of proportionality .12 9.3 Residual flexural tensile strength 13 10 Test report 14 11 Precision.15 Anne

14、x A (informative) Expressions for limit of proportionality and for residual flexural tensile strength.16 PageEN 14651:2005+A1:2007 (E) 3 Foreword This document (EN 14651:2005+A1:2007) has been prepared by Technical Committee CEN/TC 229 “Precast concrete products”, the secretariat of which is held by

15、 AFNOR. This document shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March 2008 and conflicting national standards shall be withdrawn at the latest by March 2008. This document includes Amendment 1, approved by CEN on

16、2007-08-16. This document supersedes EN 14651:2005. The start and finish of text introduced or altered by amendment is indicated in the text by tags ! “. This standard is one of a series concerned with testing metallic fibered concrete. According to the CEN/CENELEC Internal Regulations, the national

17、 standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Pola

18、nd, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 14651:2005+A1:2007 (E) 4 1 Scope This European Standard specifies a method of measuring the flexural tensile strength of metallic fibered concrete on moulded test specimen. The method provides for the determ

19、ination of the limit of proportionality (LOP) and of a set of residual flexural tensile strength values. This testing method is intended for metallic fibres no longer than 60 mm. The method can also be used for a combination of metallic fibres and, a combination of metallic fibres with other fibres.

20、 2 Normative references The following referenced documents are indispensable for the 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. EN 12350-1, Testing fresh

21、 concrete Part 1: Sampling. EN 12390-1, Testing hardened concrete Part 1: Shape, dimensions and other requirements for specimens and moulds. EN 12390-2, Testing hardened concrete Part 2: Making and curing specimens for strength tests. EN 12390-4, Testing hardened concrete Part 4: Compressive strengt

22、h Specification for testing machines. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 crack mouth opening displacement linear displacement measured by a transducer installed as specified in 7.1 and illustrated in Figure 4, on a prism subjecte

23、d to a centre-point load F 3.2 deflection linear displacement measured by a transducer installed as specified in 7.1 and illustrated in Figure 5, on a prism subjected to a centre-point load F 3.3 limit of proportionality stress at the tip of the notch which is assumed to act in an uncracked mid-span

24、 section, with linear stress distribution, of a prism subjected to the centre-point load FLdefined in 8.2 3.4 residual flexural tensile strength fictitious stress at the tip of the notch which is assumed to act in an uncracked mid-span section, with linear stress distribution, of a prism subjected t

25、o the centre-point load Fjcorresponding to CMODjwhere CMODj CMODFLor to jwhere j FL(j = 1,2,3,4) EN 14651:2005+A1:2007 (E) 5 4 Symbols and abbreviated terms 4.1 Symbols CMODFLCMOD at LOP CMODjvalue of CMOD, j = 1, 2, 3 or 4 F load Fjload value, j = 1, 2, 3 or 4 FLload at LOP L length of test specime

26、n M bending moment Mjbending moment value, j = 1, 2, 3 or 4 MLbending moment corresponding to the load at LOP b width of test specimen fR,jresidual flexural tensile strength, j = 1, 2, 3 or 4 fct,Lf LOP hspdistance between the tip of the notch and the top of the test specimen in the mid-span section

27、 l length of span x width of notch y distance between bottom of test specimen and axis of displacement transducer deflection FLdeflection at LOP jdeflection value, j = 1, 2, 3 or 4 4.2 Abbreviations CMOD crack mouth opening displacement LOP limit of proportionality EN 14651:2005+A1:2007 (E) 6 5 Prin

28、ciple The tensile behaviour of metallic fibre concrete is evaluated in terms of residual flexural tensile strength values determined from the load-crack mouth opening displacement curve or load-deflection curve obtained by applying a centre-point load on a simply supported notched prism. 6 Apparatus

29、 6.1 Saw with rotating carborundum or diamond blade with adjustable and fixable cutting depth and 90 direction of saw-cut to the specimens lengths for notching the test specimens. 6.2 Calliper, capable of reading the dimensions of test specimens to an accuracy of 0,1 mm. 6.3 Rule, capable of reading

30、 the dimensions of test specimens to an accuracy of 1 mm. 6.4 Testing machine meeting the machine class 1 requirements in EN 12390-4, capable of operating in a controlled manner i.e. producing a constant rate of displacement (CMOD or deflection), and with sufficient stiffness to avoid unstable zones

31、 in the load-CMOD curve or load-deflectioncurve. 6.5 Device for transmitting the load of the testing machine to the test specimen, made up of two supporting rollers and one loading roller (see Figure 1). Key 1 Supporting roller 2 Loading roller Figure 1 Arrangement of loading of test specimen All ro

32、llers shall be manufactured from steel and shall have a circular cross-section with a diameter of 30 mm 1 mm. They shall be at least 10 mm longer than the width of the test specimen. They shall have a clean and smooth surface. Two rollers, including the upper one, shall be capable of rotating freely

33、 around their axis and of being inclined in a plane perpendicular to the longitudinal axis of the test specimen. The distance between the centres of the supporting rollers (i.e. the span length) shall be equal to 500 mm. All rollers shall be adjusted to their correct position with all distances havi

34、ng an accuracy of 2,0 mm. 6.6 Load measuring device, capable of measuring loads to an accuracy of 0,1 kN. EN 14651:2005+A1:2007 (E) 7 6.7 Linear displacement transducer(s), capable of measuring displacements to an accuracy of 0,01 mm. 6.8 Device (frame or jig) for mounting displacement transducer(s)

35、, capable of being installed in a manner that ensures accurate determination of net mid-span deflections excluding any effects due to seating or twisting of the test specimen on its supports (only if deflection is measured instead of CMOD). 6.9 Data recording system coupled directly to electronic ou

36、tputs of load and CMOD or deflection, with a recording rate not less than 5 Hz. 7 Test specimens 7.1 Shape and size of test specimens The test specimens shall be prisms conforming to EN 12390-1 with a nominal size (width and depth) of 150 mm and a length L so that 550 mm L 700 mm. The specified shap

37、e and size of test specimens are suitable for concrete with maximum size of aggregate no larger than 32 mm and/or metallic fibres no longer than 60 mm. 7.2 Manufacture and curing of test specimens The test specimens shall be cast and cured in compliance with EN 12350-1 and EN 12390-2 unless specifie

38、d otherwise. The procedure for filling the mould is indicated in Figure 2; the size of increment 1 should be twice that of increment 2. The mould shall be filled up to approximately 90 % of the height of the test specimen before compaction. The mould shall be topped up and levelled off while being c

39、ompacted. Compaction shall be carried out by external vibration. In the case of self-compacting metallic fibre concrete, the mould shall be filled and levelled off without any compaction. Key 1 and 2 order of filling Figure 2 Procedure for filling the mould 7.3 Notching of test specimens Wet sawing

40、shall be used to notch the test specimens. Specimens shall be rotated over 90 around their longitudinal axis and then sawn through the width of specimen at mid-span (see Figure 3). EN 14651:2005+A1:2007 (E) 8 Key 1 Top surface during casting 2 Notch 3 Cross-section of test specimen Figure 3 Position

41、 of the notch sawn into the test specimen before rotating The width of the notch shall be 5 mm or less, the distance hspshall be 125 mm 1 mm (see Figure 4). The test specimens shall be cured according to EN 12390-2, unless specified otherwise, for a minimum of 3 days after sawing until no more than

42、3 h before testing (leaving sufficient time for preparation including any location devices for the transducer(s). Testing shall normally be performed at 28 days. 8 Testing procedure 8.1 Preparation and positioning of test specimens The average width of the specimen and distance between the tip of th

43、e notch and the top of the specimen in the mid-span section shall be determined from two measurements to the nearest 0,1 mm of width and distance in the notched part of the test specimen, using callipers. When the crack (or notch) mouth opening displacement is measured, a displacement transducer sha

44、ll be mounted along the longitudinal axis at the mid-width of the test specimen, such that the distance y between the bottom of the specimen and the line of measurement is 5 mm or less (see Figure 4). EN 14651:2005+A1:2007 (E) 9 Dimensions in millimetres section A-A Key 1 Detail (notch) 2 Transducer

45、 (clip gauge) 3 Knife edge Figure 4 Typical arrangement for measuring CMOD When the deflection is measured instead of the CMOD, a typical arrangement is as follows. A displacement transducer shall be mounted on a rigid frame that is fixed to the test specimen at mid-height over the supports (see Fig

46、ure 5). One end of the frame should be fixed to the specimen with a sliding fixture and the other end with a rotating fixture. Since the transducer should measure the deflection, a thin plate fixed at one end can be placed at mid-width across the notch mouth at the point of measurement (see Figure 5

47、). All bearing surfaces shall be wiped clean and any loose grit or other extraneous material from the surfaces of the test specimen that will be in contact with the rollers shall be removed. EN 14651:2005+A1:2007 (E) 10 The test specimen shall be placed in the testing machine, correctly centred and

48、with the longitudinal axis of the specimen at right angles to the longitudinal axis of the upper and lower rollers. 8.2 Bending test Before the bending test, the average span length of the test specimen shall be determined from two measurements to the nearest mm of the axis distance between the supp

49、orting rollers on both sides of the specimen, using a ruler. Dimensions in millimetres section A-A Key 1 Sliding fixture 2 Rotating fixture 3 Rigid frame EN 14651:2005+A1:2007 (E) 11 Key 1 1 mm thick aluminium plate 2 Transducer (linear variable differential transformer) 3 Spring shaft Figure 5 Typical arrangement for measuring deflection The load shall not be applied until all loading and supporting rollers are resting evenly against the test specimen. In case of a testing machine controlling the rate of increase of C