BS EN 12390-13-2013 Testing hardened concrete Determination of secant modulus of elasticity in compressio《硬化混凝土测试 正割压缩弹性模量》.pdf

1、BSI Standards PublicationBS EN 12390-13:2013Testing hardened concretePart 13: Determination of secant modulusof elasticity in compressionBS EN 12390-13:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 12390-13:2013.The UK participation in its preparation was

2、 entrusted to TechnicalCommittee B/517/1, Concrete production and testing.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctappl

3、ication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 78114 8ICS 91.100.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Commit

4、tee on 30 November 2013.Amendments issued since publicationDate Text affectedBS EN 12390-13:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12390-13 October 2013 ICS 91.100.30 English Version Testing hardened concrete - Part 13: Determination of secant modulus of elasticity in compression E

5、ssais pour bton durci - Partie 13: Dtermination du module scant dlasticit en compression Prfung von Festbeton - Teil 13: Bestimmung des Elastizittsmoduls unter Druckbelastung (Sekantenmodul)This European Standard was approved by CEN on 21 September 2013. CEN members are bound to comply with the CEN/

6、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 national standards may be obtained on application to the CEN-CENELEC Management Cent

7、re 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 notified to the CEN-CENELEC Management Centre has the same status as the

8、 official versions. 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, Netherl

9、ands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All right

10、s of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12390-13:2013 EBS EN 12390-13:2013EN 12390-13:2013 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Terms and definitions, symbols and scripts 4 4 Principle 6 5 Apparatus .6 6 T

11、est specimens 7 7 Method 7 8 Calculation of secant modulus of elasticity . 12 9 Test report . 13 10 Precision 13 Bibliography . 14 BS EN 12390-13:2013EN 12390-13:2013 (E) 3 Foreword This document (EN 12390-13:2013) has been prepared by Technical Committee CEN/TC 104 “Concrete and related products”,

12、the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by April 2014, and conflicting national standards shall be withdrawn at the latest by April 2014. Attention is

13、 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. It is based on an extensive investigation and comparison of existing National Standards: ASTM, BS,

14、 DIN, ISO, NORD TEST and UNI followed by the analysis of a test programme involving five laboratories carried out by UNI. This standard is one of a series concerned with testing concrete. The series EN 12390, Testing hardened concrete, consists of the following parts: Part 1: Shape, dimensions and o

15、ther requirements of specimens and moulds Part 2: Making and curing specimens for strength tests Part 3: Compressive strength of test specimens Part 4: Compressive strength - Specification for testing machines Part 5: Flexural strength of test specimens Part 6: Tensile splitting strength of test spe

16、cimens Part 7: Density of hardened concrete Part 8: Depth of penetration of water under pressure Part 13: Determination of secant modulus of elasticity in compression According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to imple

17、ment this European Standard: 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,

18、 Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 12390-13:2013EN 12390-13:2013 (E) 4 1 Scope This European Standard specifies the method for the determination of the secant modulus of elasticity in compression of hardened concrete on test specimens which may be c

19、ast or taken from a structure. The test method allows the determination of two secant moduli of elasticity: the initial modulus, EC,0measured at first loading and the stabilized modulus, EC,Smeasured after three loading cycles. Two different test methods are given. The first (method A) is for determ

20、ination of both initial and stabilized moduli, the second (method B) is for determination of stabilized modulus only. 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

21、 the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 12390-1, Testing hardened concrete Part 1: Shape, dimensions and other requirements of specimens and moulds EN 12390-2, Testing hardened concrete Part 2: Making an

22、d curing specimens for strength tests EN 12390-3, Testing hardened concrete Part 3: Compressive strength of test specimens EN 12390-4, Testing hardened concrete Part 4: Compressive strength Specification for testing machines EN 12504-1:2009, Testing concrete in structures Part 1: Cored specimens Tak

23、ing, examining and testing in compression EN ISO 9513, Metallic materials Calibration of extensometer systems used in uniaxial testing (ISO 9513) 3 Terms and definitions, symbols and scripts 3.1 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1.1

24、 initial secant modulus of elasticity EC,0secant slope of the stress strain curve at first loading 3.1.2 stabilized secant modulus of elasticity EC,Ssecant slope of the stress strain curve after three loading cycles 3.1.3 base or gauge length length used as reference base for strain measurement 3.1.

25、4 measuring line straight line laying on the lateral surface of the specimen and parallel to the vertical axis (see Figure 1) BS EN 12390-13:2013EN 12390-13:2013 (E) 5 Key 1 measuring line Figure 1 Measuring line on cylinder and prismatic specimens 3.2 Symbols and scripts For the purposes of this Eu

26、ropean Standard, the symbols and scripts in Table 1 apply. Table 1 Symbols and scripts (1 of 2) Symbol Explanation EC,0Initial secant modulus of elasticity EC,SStabilized secant modulus of elasticity Measured strain L Change in measured length L0Initial gauge length of instrument L Specimen length d

27、 Specimen diameter or width D Upper sieve size (for definition of aggregates size, see EN 12620) DmaxDeclared value of D of the coarsest fraction of aggregates actually used in the concrete fcCompressive strength of concrete determined by testing companion specimens cylinders, prisms, cubes or cores

28、 or estimated from non-destructive tests aNominal upper stress = fc/ 3 bNominal lower stress arbitrary value between 10 % and 15 % of fcpNominal preload stress arbitrary value between 0,5 MPa and baStrain along each measuring line at upper stress bStrain along each measuring line at lower stress pSt

29、rain along each measuring line at preload stress a, nAverage strain at upper stress on loading cycle n b, nAverage strain at lower stress on loading cycle n BS EN 12390-13:2013EN 12390-13:2013 (E) 6 Table 1 (2 of 2) Symbol Explanation p, nAverage strain at preload stress on loading cycle n ma Measur

30、ed stress corresponding to nominal upper stress, amb Measured stress corresponding to nominal lower stress, bmp Measured stress corresponding to nominal preload stress, p Difference between measured stresses ma and mb (Method A) or ma and mp (Method B) 0Strain difference during first loading cycle s

31、Strain difference during third loading cycle 4 Principle A test specimen is loaded under axial compression, the stresses and strains are recorded and the slope of the secant to the stress-strain curve is determined at first loading (Method A only) and after three loading cycles (Methods A and B). Th

32、e secant slope is known as the secant modulus of elasticity in compression. The test specimens may be either cast or taken from an existing structure. 5 Apparatus 5.1 Test machine Compression testing machine conforming to EN 12390-4 with following additional requirements: a) suitable for execution o

33、f programmable loading cycles; b) able to increase and decrease the load at a constant rate within a given tolerance (see 7.3.1 and 7.3.2); c) able to maintain a constant load at selectable nominal values with a maximum variation within 5 %; d) calibrated as Class 1 to EN 12390-4 over the working ra

34、nge from the lower stress to the upper stress as defined in 7.3.1 and 7.3.2 . NOTE The test lends itself to the use of automatic control test machines. However, if manual control test machines can be shown to comply with b), c) and d) above, they can be used. 5.2 Instrumentation Instrumentation meas

35、uring the strain of the specimen under axial compression along a measuring line shall be Class 2 as determined in accordance with EN ISO 9513 in the range from 0 m/m to 1 000 m/m. The instrumentation can measure strain directly (e.g. resistive strain gauges) or take the form of measuring length chan

36、ge from which the strain, , is calculated with the formula: 0LL = (1) BS EN 12390-13:2013EN 12390-13:2013 (E) 7 5.3 Base or gauge length The base or gauge length of the strain measuring instrument shall be between two-thirds of the specimen diameter (or section width) and one-half of the specimen le

37、ngth and not less than 3Dmax. NOTE For specimens where L/d is between 3,5 and 4,0, the gauge length can be increased to up to 2/3 of the specimen length. 6 Test specimens 6.1 Shape and dimensions of specimens The test specimens shall be moulded (cylinder or prism) or drilled cores complying with the

38、 requirements of EN 12390-1 or EN 12504-1. The dimension d (diameter or width) shall be at least 3,5 times Dmax. The ratio between the specimen length L and the dimension d shall be in the range 2 L/d 4. The recommended test specimen shall be cylinders of diameter 150 mm and height 300 mm (reference

39、 specimen). Alternatively, other test specimens generally complying with the requirements of EN 12390-1 may be used, provided that the specimen complies with the dimensions and aggregate size to diameter or width stated above. In the case of specimens drilled or cut from a structure, this requiremen

40、t sometimes cannot be fulfilled; in such cases, this shall be stated in the test report. NOTE The size of the test specimen can have an influence on the result. If relevant, the adjustment of test specimen shall comply with EN 12390-3. Companion specimens should be available for the determination of

41、 compressive strength as described in 7.2 and shall be made from the same batch of concrete in the case of cast specimens, or shall be drilled from the same zone in the case of drilled specimens. 6.2 Curing, storage and conditioning Moulded specimens shall be cured or stored in accordance with EN 12

42、390-2, cored specimen in accordance with EN 12504-1. Before testing they shall be maintained at (20 2) C for sufficient time for strain measuring instruments to be securely fixed but not longer than 24 h out of water. During the time out of water, precautions shall be taken to ensure the specimen re

43、mains moist. 7 Method 7.1 Specimen instrumentation and positioning The strain measuring instruments shall be positioned in such a way that the measuring base is at equivalent distance from the end faces of the specimen. At least two strain measuring instruments shall be symmetrically arranged with r

44、espect to the central axis of the specimen. The specimen shall be centred on the lower platen. 7.2 Determination of compressive strength The compressive strength of concrete fcshall be determined in accordance with EN 12390-3 on companion specimen(s) preferably having the same size and shape of thos

45、e specimens used for secant modulus of elasticity determination. BS EN 12390-13:2013EN 12390-13:2013 (E) 8 If the companion specimens are not of the same size and shape as the specimen used for the determination of secant modulus of elasticity, the difference in compressive strength obtained from sp

46、ecimens of different shape and sizes shall be taken into account. The compressive strength (measured or estimated), fcis used to define the stress levels of the test cycle for the determination of secant modulus of elasticity. If companion test specimens for the determination of compressive strength

47、 are not available, the compressive strength may be estimated from non-destructive tests or by national provisions valid in the place of use of the concrete. Details of the test method and results from the non-destructive method adopted shall be indicated in the test report. 7.3 Determination of sec

48、ant modulus of elasticity 7.3.1 Method A Determination of initial and stabilized secant modulus of elasticity 7.3.1.1 Preloading cycles Three preloading cycles are carried out in order to check the wiring stability (first check) and specimen positioning (second check). Place the test specimen, with

49、the measuring instruments attached axially, centrally in the testing machine. For the first loading cycle, apply stress to the specimen at a rate of (0,6 0,2) MPa/s up to the lower stress b. Hold the lower stress within 5 % of the nominal value for a period not exceeding 20 s. Record the lower stress mb . Reduce the stress at a rate of (0,6 0,2) MPa/s down to the preload stress p. Hold the preload stress for a period not exceeding 20 s. At the end of this period, zero the stra