1、BRITISH STANDARDBS EN 14651:2005 +A1:2007Test method for metallic fibre concrete Measuring the flexural tensile strength (limit of proportionality (LOP), residual)ICS 91.100.30g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g
2、3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 14651:2005+A1:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 11 July 2005 BSI 2008ISBN 978 0 580 61052 3National forewordThis British Standard is the UK im
3、plementation of EN 14651:2005+A1:2007. It supersedes BS EN 14651:2005 which is withdrawn.The start and finish of text introduced or altered by amendment is indicated in the text by tags. Tags indicating changes to CEN text carry the number of the CEN amendment. For example, text altered by CEN amend
4、ment A1 is indicated by !“.The UK participation in its preparation was entrusted to Technical Committee B/524, Precast concrete products.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary pr
5、ovisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since publicationDate Comments31 March 2008 Implementation of CEN amendment A1:2007EUROPEAN STANDARD NORME EUROPENN
6、E EUROPISCHE NORM EN 14651:2005+A1 September 2007 ICS 91.100.30 Supersedes EN 14651:2005 English Version Test method for metallic fibre concrete - Measuring the flexural tensile strength (limit of proportionality (LOP), residual) Mthode dessai du bton de fibres mtalliques - Mesurage de la rsistance
7、la traction par flexion (limite de proportionnalit (LOP), rsistance rsiduelle) Prfverfahren fr Beton mit metallischen Fasern - Bestimmung der Biegezugfestigkeit (Proportionalittsgrenze, residuelle Biegezugfestigkeit) This European Standard was approved by CEN on 3 April 2005 and includes Amendment 1
8、 approved by CEN on 16 August 2007. 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 nat
9、ional standards may be obtained on application to the CEN 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
10、 notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembour
11、g, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights
12、 of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14651:2005+A1:2007: E2 Contents page 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 Appar
13、atus .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 of 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
14、deflection.11 9.2 Limit of proportionality .12 9.3 Residual flexural tensile strength 13 10 Test report 14 11 Precision.15 Annex A (informative) Expressions for limit of proportionality and for residual flexural tensile strength.16 BS EN 14651:2005+A1:20073 Foreword This document (EN 14651:2005+A1:2
15、007) has been prepared by Technical Committee CEN/TC 229 “Precast concrete products”, the secretariat of which is held by 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 n
16、ational standards shall be withdrawn at the latest by March 2008. This document includes Amendment 1, approved by CEN on 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
17、 series concerned with testing metallic fibered concrete. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, F
18、rance, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. BS EN 14651:2005+A1:20074 1 Scope This European Standard specifies a method of measuring
19、the flexural tensile strength of metallic fibered concrete on moulded test specimen. The method provides for the determination 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. Th
20、e method can also be used for a combination of metallic fibres and, a combination of metallic fibres with other fibres. 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
21、references, the latest edition of the referenced document (including any amendments) applies. EN 12350-1, Testing fresh 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 Pa
22、rt 2: Making and curing specimens for strength tests. EN 12390-4, Testing hardened concrete Part 4: Compressive strength 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 line
23、ar displacement measured by a transducer installed as specified in 7.1 and illustrated in Figure 4, on a prism subjected 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-po
24、int load F 3.3 limit of proportionality 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 to the centre-point load FLdefined in 8.2 3.4 residual flexural tensile strength fictitious stress at the tip of the
25、notch which is assumed to act in an uncracked mid-span section, with linear stress distribution, of a prism subjected to the centre-point load Fjcorresponding to CMODjwhere CMODj CMODFLor to jwhere j FL(j = 1,2,3,4) BS EN 14651:2005+A1:20075 4 Symbols and abbreviated terms 4.1 Symbols CMODFLCMOD at
26、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 specimen 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
27、, 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 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.
28、2 Abbreviations CMOD crack mouth opening displacement LOP limit of proportionality BS EN 14651:2005+A1:20076 5 Principle 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
29、 or load-deflection curve obtained by applying a centre-point load on a simply supported notched prism. 6 Apparatus 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 C
30、alliper, capable of reading the dimensions of test specimens to an accuracy of 0,1 mm. 6.3 Rule, capable of reading 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. pr
31、oducing a constant rate of displacement (CMOD or deflection), and with sufficient stiffness to avoid unstable zones 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 roll
32、er (see Figure 1). Key 1 Supporting roller 2 Loading roller Figure 1 Arrangement of loading of test specimen All rollers 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. Th
33、ey shall have a clean and smooth surface. Two rollers, including the upper one, shall be capable of rotating freely 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 spa
34、n length) shall be equal to 500 mm. All rollers shall be adjusted to their correct position with all distances having an accuracy of 2,0 mm. 6.6 Load measuring device, capable of measuring loads to an accuracy of 0,1 kN. BS EN 14651:2005+A1:20077 6.7 Linear displacement transducer(s), capable of mea
35、suring displacements to an accuracy of 0,01 mm. 6.8 Device (frame or jig) for mounting displacement transducer(s), 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 suppo
36、rts (only if deflection is measured instead of CMOD). 6.9 Data recording system coupled directly to electronic outputs 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 1
37、2390-1 with a nominal size (width and depth) of 150 mm and a length L so that 550 mm L 700 mm. The specified shape 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
38、specimens The test specimens shall be cast and cured in compliance with EN 12350-1 and EN 12390-2 unless specified 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 %
39、of the height of the test specimen before compaction. The mould shall be topped up and levelled off while being compacted. 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.
40、 Key 1 and 2 order of filling Figure 2 Procedure for filling the mould 7.3 Notching of test specimens Wet sawing 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). BS EN
41、14651:2005+A1:20078 Key 1 Top surface during casting 2 Notch 3 Cross-section of test specimen Figure 3 Position 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 cure
42、d according to EN 12390-2, unless specified otherwise, for a minimum of 3 days after sawing until no more than 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 Pre
43、paration and positioning of test specimens The average width of the specimen and distance between the tip of the 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, u
44、sing callipers. When the crack (or notch) mouth opening displacement is measured, a displacement transducer shall 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
45、 Figure 4). BS EN 14651:2005+A1:20079 Dimensions in millimetres section A-A Key 1 Detail (notch) 2 Transducer (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
46、shall be mounted on a rigid frame that is fixed to the test specimen at mid-height over the supports (see Figure 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
47、 fixed at one end can be placed at mid-width across the notch mouth at the point of measurement (see Figure 5). 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.
48、BS EN 14651:2005+A1:200710 The test specimen shall be placed in the testing machine, correctly centred and 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
49、 specimen shall be determined from two measurements to the nearest mm of the axis distance between the supporting 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 BS EN 14651:2005+A1:200711 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 even
