1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12350-12:2010Testing fresh concretePart 12: Self-compacting concrete J-ringtestBS EN 12350-12:2010 BRITISH STANDARDNational forewordThis British Standard is the UK implemen
2、tation of EN 12350-12:2010.The UK participation in its preparation was 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 necess
3、aryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 69216 1ICS 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 31 August 2010Amendments issued since publicationDate Text affectedBS EN 12350-12:2010EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12350-12 July 2010 ICS 91.100.30 English Version Testing fresh concrete - Part 12: Self-compacting concrete - J-ring test Essai pour bton frais - Partie 1
5、2 : Bton auto-plaant - Essai dcoulement lanneau Prfung von Frischbeton - Teil 12: Selbstverdichtender Beton - Blockierring-Versuch This European Standard was approved by CEN on 20 June 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for
6、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 Management Centre or to any CEN member. This European Standard exists in three official
7、 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 Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Be
8、lgium, Bulgaria, Croatia, 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 CO
9、MMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12350-12:2010: EBS EN 12350-12:2010
10、EN 12350-12:2010 (E) 2 Contents Page Foreword 31 Scope 52 Normative references 53 Principle 54 Apparatus .55 Test sample 76 Procedure .77 Expression of results 88 Test report 89 Repeatability and reproducibility .9Bibliography . 10BS EN 12350-12:2010EN 12350-12:2010 (E) 3 Foreword This document (EN
11、12350-12:2010) has been prepared by Technical Committee CEN/TC 104 “Concrete and related products”, 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 January
12、 2011, and conflicting national standards shall be withdrawn at the latest by January 2011. 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 identifying any or all such patent ri
13、ghts. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). This standard is based on the results from the EU-project “Testing-SCC“ under the 5thFrame Programme (GRD2-20
14、00-30024/G6RD-CT-2001-00580). Owing to its significant advantages in the improvement of construction quality and working environment, self-compacting concrete (SCC) has been widely accepted by the construction owners. The use of SCC in practical concrete construction is steadily increasing. Since SC
15、C has to give satisfactory in-situ properties (perfect filling of the mould and embedment of the reinforcement, homogeneity and full compaction) without vibration, the proper methods for testing fresh SCC are very important. The consistence of fresh SCC should basically include three key properties:
16、 filling ability, passing ability and resistance to segregation. It is desirable, especially in the case of new constituents or new concrete compositions, to test the consistence of fresh SCC before casting in place. A number of test methods including this test are available for testing fresh SCC. M
17、ost of the commonly used test methods were evaluated in the recently closed EU-project “Testing-SCC“ under the 5thFrame Programme (GRD2-2000-30024/G6RD-CT-2001-00580). According to the results from this EU project, it seems no single test method can completely cover all the three key properties. Nev
18、ertheless any test method should at least be correlated to the practical situation and give consistent results in order to provide reliable data for judgment of concrete workability. This standard is one of a series concerned with testing fresh concrete. EN 12350, Testing fresh concrete, consists of
19、 the following parts: Part 1: Sampling Part 2: Slump-test Part 3: Vebe test Part 4: Degree of compactability Part 5: Flow table test Part 6: Density Part 7: Air content Pressure methods Part 8: Self-compacting concrete Slump-flow test BS EN 12350-12:2010EN 12350-12:2010 (E) 4 Part 9: Self-compacting
20、 concrete V-funnel test Part 10: Self-compacting concrete L box test Part 11: Self-compacting concrete Sieve segregation test Part 12: Self-compacting concrete J-ring test CAUTION When cement is mixed with water, alkali is released. Take precautions to avoid dry cement entering the eyes, mouth and n
21、ose whilst mixing concrete. Prevent skin contact 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. Accord
22、ing to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Ital
23、y, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 12350-12:2010EN 12350-12:2010 (E) 5 1 Scope This European Standard specifies the procedure for determining the passing ability (measur
24、ed by the blocking step), the flow spread and t500Jflow time of self-compacting concrete as the concrete flows through the J-ring. The test is not suitable when the maximum size of aggregate exceeds 40 mm. NOTE In respect to the relationship between aggregate size and bar spacing, the test is intend
25、ed to assess the passing ability of the concrete proposed with the bar spacing typically in the works. If the concrete blocks then the aggregate size could be too large for the particular application. 2 Normative references The following referenced documents are indispensable for the application of
26、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 concrete Part 1: Sampling EN 12350-8, Testing fresh concrete Part 8: Self-compacting concrete Slump
27、-flow test 3 Principle The J-ring test is used to assess the passing ability of self-compacting concrete to flow through tight openings including spaces between reinforcing bars and other obstructions without segregation or blocking. A narrow and wide bar spacing test is described. The narrow bar sp
28、acing simulates more congested reinforcement. The J-ring test is an alternative to the L box test EN 12350-10 although the result is not directly comparable. The method follows the procedure detailed in EN 12350-8 except that, before filling the slump cone with concrete, the J-ring, consisting of a
29、ring of evenly spaced vertical smooth bars, is placed over the cone. In addition, the time when the concrete has flowed to a diameter of 500 mm t500J shall be measured, when specified. 4 Apparatus The apparatus shall be in accordance with EN 12350-8 with the additional items as detailed below: NOTE
30、The feet to the slump cone may be removed to fit inside the J-ring or if their presence prevents free upward movement from within the J-ring. 4.1 Narrow gap J-ring. Smooth steel bars, (18 0,5) mm , secured to a ring (300 2) mm diameter (bar spacing of (41 1) mm) with the dimensions as shown in Figur
31、es 1 and 2. 4.2 Wide gap J-ring. Smooth steel bars, (18 0,5) mm , secured to a ring (300 2) mm diameter (bar spacing of (59 1) mm) with the dimensions as shown in Figures 1 and 3. BS EN 12350-12:2010EN 12350-12:2010 (E) 6 4.3 Straight edge. Straight edge for aligning the reference line for the heigh
32、t measurements, with a length of about 400 mm. Dimensions in millimetres Key 1 Slump cone 2 J-ring 3 Baseplate 4 Concrete h Difference in height between top of J-ring and top of the concrete at points referenced Figure 1 Section A-A across J-ring Dimensions in millimetres Key a 16 equally spaced smo
33、oth steel bars ( 0,5 mm) h Difference in height between top of J-ring and top of the concrete at points referenced Figure 2 Narrow gap J-ring BS EN 12350-12:2010EN 12350-12:2010 (E) 7 Dimensions in millimetres Key a 12 equally spaced smooth steel bars ( 0,5 mm) h Difference in height between top of
34、J-ring and top of the concrete at points referenced Figure 3 Wide gap J-ring 5 Test sample The sample shall be obtained in accordance with EN 12350-1 6 Procedure Prepare the cone and baseplate as described in EN 12350-8. Place the cone centrally within the 210 mm circle on the baseplate and hold in
35、position (or use the weighted collar), ensuring that no concrete can leak from under the cone. Place the J-ring on the base plate, concentrically around the cone. Fill the cone in one operation without any agitation or mechanical compaction, and strike off surplus from the top of the cone. Allow the
36、 filled cone to stand for not more than 30 s; during this time remove any spilled concrete from the baseplate and ensure the baseplate is damp all over but without any surplus water. Lift the cone vertically in 1 s to 3 s in one movement without interfering with the flow of concrete. If the t500Jtim
37、e has been requested, start the stop watch immediately the cone ceases to be in contact with the baseplate and record the time taken to the nearest 0,1 s for the concrete to reach the 500 mm circle at any point. Without disturbing the baseplate or concrete, measure the largest diameter of the flow s
38、pread and record as d1to the nearest 10 mm. Then measure the diameter of the flow spread at right angles to d1to the nearest 10 mm and record as d2to the nearest 10 mm. Lay the straight edge on the top side of the J-ring and measure the relative height differences between the lower edge of the strai
39、ght edge and the concrete surface at the central position h0and at the four positions outside the J-ring, two hx1, hx2in the x-direction and the other two hy1, hy2in the y-direction (perpendicular to x), as shown in Figures 2 and 3, measured to the nearest 1 mm. BS EN 12350-12:2010EN 12350-12:2010 (
40、E) 8 Check the concrete spread for signs of segregation and report under item 8, h) in a qualitative way, e.g. no indication of segregation, strong indication of segregation. NOTE Signs of segregation include a ring of cement paste/mortar and segregated coarse aggregate in the central area. 7 Expres
41、sion of results 7.1 Passing ability PJ The J-ring passing ability PJ, measured by the blocking step, is calculated using the equation below and expressed to the nearest 1 mm. ( )021214hhhhhPJyyxx+= where PJ is the passing ability, measured by the blocking step, in millimetres; h are the measurement
42、heights, in millimetres. 7.2 Flow spread SFJThe J-ring flow spread SFJis the mean of d1and d2, expressed to the nearest 10 mm given by the following equation: 2)(21JddSF+= where SFJis the flow spread, in millimetres; d1is the largest diameter of flow spread, in millimetres; d2 is theflow spread at 9
43、0 to d1, in millimetres. 7.3 Flow time t500JThe J-ring flow time t500Jis the period between the moment the cone leaves the base plate and SCC first touches the circle of diameter 500 mm. The time t500Jis expressed in seconds to the nearest 0,5 s. 8 Test report The test report shall include: a) ident
44、ification of the test sample; b) location where the test was performed; c) date and time of test; d) whether narrow or wide gap J-ring used; BS EN 12350-12:2010EN 12350-12:2010 (E) 9 e) passing ability PJ, measured by the blocking step, to the nearest 1 mm; f) flow spread SFJ,to the nearest 10 mm; g
45、) t500Jtime, to the nearest 0,5 s (when requested); h) any indication of segregation of the concrete; i) any deviation from the standard test method; j) declaration by the person technically responsible for the test that it was carried out in accordance with this document, except as noted in item i)
46、. The report may include: k) temperature of the concrete at the time of test; l) age of concrete at time of test (if known). 9 Repeatability and reproducibility The repeatability r and the reproducibility R have been determined for the narrow gap J-ring by a programme including eight laboratories, 1
47、6 operators and two replicates, and interpreted in accordance with ISO 5725-2. The resulting values for r and R when using the narrow gap J-ring are given in Tables 1, 2 and 3. No data exists for the wide gap J-ring. Table 1 Repeatability and reproducibility for typical values of the narrow gap J-ri
48、ng passing ability PJ, measured by the blocking step J-ring passing ability PJ, measured by the blocking step, in millimetres 20 20 Repeatability r in millimetres 4,6 7,8 Reproducibility R in millimetres 4,9 7,8Table 2 Repeatability and reproducibility for typical values of the narrow gap J-ring flo
49、w spread SFJJ-ring flow spread SFJin millimetres 750 Repeatability r in millimetres 59 46 25 Reproducibility R in millimetres 67 46 31 Table 3 Repeatability and reproducibility for typical values of the narrow gap J-ring flow time t500JJ-ring flow time t500Jin seconds 3,5 3,5 6 6 Repeatability r in seconds 0,70 1,23 4,34 Reproducibility R in seconds 0,90 1,32 4,34 BS EN 12350-12:2010EN 12350-12:2010 (E) 10 Bibliography 1 EN 12350-2, Te
