BS EN 12350-6-2009 Testing fresh concrete - Density《新拌混凝土试验 密度》.pdf

1、BS EN12350-6:2009ICS 91.100.30NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDTesting fresh concretePart 6: DensityThis British Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 31 May 2009 BSI 2009ISBN 978 0 580 58793 1Ame

2、ndments/corrigenda issued since publicationDate CommentsBS EN 12350-6:2009National forewordThis British Standard is the UK implementation of EN 12350-6:2009. Itsupersedes BS EN 12350-6:2000 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee B/517/1, Concre

3、te 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 provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cann

4、ot confer immunityfrom legal obligations.BS EN 12350-6:2009EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 12350-6April 2009ICS 91.100.30 Supersedes EN 12350-6:1999 English VersionTesting fresh concrete - Part 6: DensityEssai pour bton frais - Partie 6: Masse volumique Prfung von Frischbeton - Tei

5、l 6: FrischbetonrohdichteThis European Standard was approved by CEN on 20 January 2009.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists

6、and bibliographical references concerning such nationalstandards 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 translationunder the responsib

7、ility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland,

8、Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: Avenue Marnix 17

9、, B-1000 Brussels 2009 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12350-6:2009: EBS EN 12350-6:2009EN 12350-6:2009 (E) 2 Contents Page Foreword 3 1 Scope 52 Normative references 53 Principle 54 Apparatus .55 Sampling .66 Procedu

10、re .67 Calculation of density .88 Test report 89 Precision .8Annex A (normative) Calibration of container . 10BS EN 12350-6:2009EN 12350-6:2009 (E) 3 Foreword This document (EN 12350-6:2009) has been prepared by Technical Committee CEN/TC 104 “Concrete and related products”, the secretariat of which

11、 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 October 2009, and conflicting national standards shall be withdrawn at the latest by October 2009. Attention is drawn to the possib

12、ility 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. This document supersedes EN 12350-6:1999. The results of a recent laboratory inter-comparison, part-funded by the EC u

13、nder the Measurement and Testing programme, contract MAT1-CT94-0043mtp, have been taken into account. The compaction of specimens using hand tamping, vibrating table, or internal (poker) vibrator are accepted as equivalent. However, the use of an internal vibrator to compact specimens containing ent

14、rained air should be carried out with caution. A procedure for calibrating the container has been included as a normative Annex A. This series EN 12350 includes the following parts. EN 12350 Testing fresh concrete Part 1: Sampling; Part 2: Slump-test; Part 3: Vebe test; Part 4: Degree of compactabil

15、ity; Part 5: Flow table test; Part 6: Density; Part 7: Air content Pressure methods; Part 8: Self-compacting concrete - Slump-flow test (in preparation); Part 9: Self-compacting concrete - V-funnel test (in preparation); Part 10: Self-compacting concrete - L-box test (in preparation); Part 11: Self-

16、compacting concrete - Sieve segregation test (in preparation); Part 12: Self-compacting concrete - J-ring test (in preparation). CAUTION When cement is mixed with water, alkali is released. Take precautions to avoid dry cement entering the eyes, mouth and nose whilst mixing concrete. Prevent skin co

17、ntact with wet cement or concrete by wearing suitable protective clothing. If cement or concrete enters the eye, immediately wash it out thoroughly with clean water and seek medical treatment without delay. Wash wet concrete off the skin immediately. BS EN 12350-6:2009EN 12350-6:2009 (E) 4 The follo

18、wing amendments have been made to the 1999-10 edition of this standard: editorial revision detailing of compaction process accuracy of balance, scales and other testing equipment. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are b

19、ound 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, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden,

20、 Switzerland and the United Kingdom. BS EN 12350-6:2009EN 12350-6:2009 (E) 5 1 Scope This European standard specifies a method for determining the density of compacted fresh concrete both in the laboratory and in the field. NOTE It may not be applicable to very stiff concrete which cannot be compact

21、ed by normal vibration. 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

22、 12350-1, Testing fresh concrete Part 1: Sampling 3 Principle Fresh concrete is compacted into a rigid and watertight container of known volume and mass and is then weighed. 4 Apparatus 4.1 Container, watertight, of sufficient rigidity to retain its shape, made of metal not readily attacked by cemen

23、t paste, having a smooth internal face, with the rim machined to a plane surface. The rim and base shall be parallel. The smallest dimension of the container shall be at least four times the maximum nominal size of the coarse aggregate in the concrete, but shall be not less than 150 mm. The volume o

24、f the container shall be not less than 5 l. 4.2 Filling frame, filling may be simplified by using a filling frame fitted tightly to the container 4.3 Means of compacting the concrete, which may be one of the following: a) internal (poker) vibrator with a minimum frequency of approximately 120 Hz (7

25、200 cycles per minute), the diameter of the internal vibrator not exceeding approximately one-quarter of the smallest dimension of the container; b) vibrating table with a minimum frequency of approximately 40 Hz (2 400 cycles per minute); c) compacting rod of circular cross-section, straight, made

26、of steel, having a diameter of approximately 16 mm, length of approximately 600 mm and with rounded ends; d) compacting bar, straight, made of steel having a square cross-section of approximately 25 mm 25 mm and length of approximately 380 mm. BS EN 12350-6:2009EN 12350-6:2009 (E) 6 4.4 Balance or s

27、cales, capable of determining the mass of the compacted concrete to an accuracy of 0,01 kg 4.5 Straight-edged scraper, made of steel, not less than 100 mm greater in length than the maximum internal dimension of the top of the container 4.6 Scoop, of approximately 100 mm width 4.7 Steel trowel or fl

28、oat 4.8 Remixing container, flat tray of rigid construction and made from a non- absorbent material not readily attacked by cement paste. It shall be of appropriate dimensions such that the concrete can be thoroughly re-mixed, using the square-mouthed shovel. 4.9 Shovel, with square mouth NOTE The s

29、quare mouth is required to ensure proper mixing of material on the remixing container. 4.10 Mallet, soft faced 5 Sampling The sample shall be obtained in accordance with EN 12350-1. The sample shall be re-mixed using the remixing container and the square mouthed shovel or equivalent remixing procedu

30、re specified in the national annex NA before carrying out the test. 6 Procedure 6.1 Calibration Calibrate the container in accordance with Annex A, to obtain the volume of the container (V). 6.2 Mass of container Weigh the container to determine its mass (m1) and record the value indicated. 6.3 Fill

31、ing the container Depending on the consistence of the concrete and the method of compaction, the container shall be filled in two or more layers to achieve full compaction, except in the case of self-compacting concrete for which the container shall be filled in one operation. If a filling frame is

32、used, the amount of concrete used to fill the mould shall be such that a layer of concrete remains in the filling frame after compaction. The thickness of this layer shall be 10 % to 20 % of the height of the container. BS EN 12350-6:2009EN 12350-6:2009 (E) 7 6.4 Compacting the concrete 6.4.1 Genera

33、l The concrete shall be compacted immediately after placing in the moulds in such a way as to produce full compaction of the concrete with neither excessive segregation nor laitance. Each layer shall be compacted by using one of the methods described in 6.4.2 or 6.4.3. In the case of self-compacting

34、 concrete, no mechanical or hand compaction shall be applied during filling or after the container is filled. NOTE 1 Full compaction is achieved using mechanical vibration, when there is no further appearance of large air bubbles on the surface of the concrete and the surface becomes relatively smoo

35、th with a glazed appearance, without excessive segregation. NOTE 2 Further guidance on methods of compaction for concretes having different consistencies or cast in different sizes of containers, may be given in national annex NA. 6.4.2 Mechanical compaction 6.4.2.1 Compacting with internal vibrator

36、 Apply the vibration for the minimum duration necessary to achieve full compaction of the concrete. Avoid over-vibration, which may cause loss of entrained air. NOTE Care should be taken not to damage the container. The use of a filling frame is recommended. Ensure that the vibrator is kept vertical

37、 and not allowed to touch the bottom or sides of the container. Laboratory tests have shown that great care is needed if loss of entrained air is to be avoided, when using an internal vibrator. 6.4.2.2 Compacting with vibrating table Apply the vibration for the minimum duration necessary to achieve

38、full compaction of the concrete. The container should preferably be attached to, or firmly held against the table. Avoid over-vibration, which may cause loss of entrained air. 6.4.3 Compacting by hand with compacting rod or bar Distribute the strokes of the compacting rod, or bar, in a uniform manne

39、r over the cross-section of the container. Ensure that the compacting rod, or bar, does not forcibly strike the bottom of the container when compacting the first layer, nor penetrate significantly any previous layer. Subject the concrete to a sufficient number of strokes per layer, typically 25 for

40、concretes having a consistence equivalent to slump classes S1 and S2, in order to remove pockets of entrapped air but not the entrained air. After compaction of each layer, tap the sides of the container smartly with the mallet until large bubbles of air cease to appear on the surface and depression

41、s left by the compacting rod or bar, are removed. 6.5 Surface levelling If a filling frame is used, remove it immediately after compaction. After the top layer has been compacted, smooth it level with the top of the container, using the steel float or trowel. Skim the surface and rim with the straig

42、htedge and wipe the outside of the container clean. 6.6 Weighing Weigh the container with its contents to determine its mass (m2) and record the value indicated. BS EN 12350-6:2009EN 12350-6:2009 (E) 8 7 Calculation of density The density is calculated from the formula: 21mmDV= where D is the densit

43、y of the fresh concrete, in kg/m; m1is the mass of the empty container, in kg; m2is the mass of the container completely filled with compacted concrete, in kg; V is the volume of the container, in m. Express the density of the fresh concrete to the nearest 10 kg/m3. 8 Test report The report shall in

44、clude: a) identification of the test sample; b) location of performance of test; c) date of test; d) method of compaction; e) calculated density of the fresh concrete, in kg/m; f) any deviation from standard test method; g) declaration by the person technically responsible for the test that it was c

45、arried out in accordance with this document, except as noted item f). The report may include: h) temperature of the concrete sample at time of test; i) time of test; j) consistence of the concrete. 9 Precision Precision data are given in Table 1. These apply to density measurements made on concrete

46、taken from the same sample and compacted by hand using a compacting bar when each test result represents a single density determination. BS EN 12350-6:2009EN 12350-6:2009 (E) 9 Table 1 Precision data for density of fresh concrete measurements Range Repeatability conditions Reproducibility conditions

47、 kg/m3Srkg/m3r kg/m3SR kg/m3R kg/m32 300 to 2 400 5,5 15 10,2 29 NOTE 1 The precision data were determined as part of an experiment in the UK in 1987 in which precision data were obtained for several of the tests described in the then BS 1881. The experiment involved 16 operators. The concretes were

48、 made using an ordinary Portland cement, Thames Valley sand, and Thames Valley 10 mm and 20 mm coarse aggregates. (Hand compaction using a compacting bar was used.) NOTE 2 The containers used complied with the requirements of BS 1881:Part 107: nominal capacity: 0,01 m3inside diameter: 200 mm 1,5 mm

49、inside height: 320 mm 1,5 mm minimum thickness of metal: 4 mm radius between wall and base: 20 mm NOTE 3 The difference between two test results from the same sample by one operator using the same apparatus within the shortest feasible time interval will exceed the repeatability value r on average not more than once in 20 cases in the normal and correct operation of the method. NOTE 4 Test results on the same sample obtained within the shortest feasible time interval by two operators each using their own apparatus