ASTM C1621 C1621M-2008 Standard Test Method for Passing Ability of Self-Consolidating Concrete by J-Ring.pdf

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1、Designation: C 1621/C 1621M 08Standard Test Method forPassing Ability of Self-Consolidating Concrete by J-Ring1This standard is issued under the fixed designation C 1621/C 1621M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the

2、year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers determination of the passingability of self-consolidating concrete by using the J-Rin

3、g incombination with a slump cone mold. The test method islimited to concrete with nominal maximum size of aggregate ofup to 1 in 25 mm.1.2 The values stated in either inch-pounds or SI units are tobe regarded separately as standard. Within the text, the SI unitsare shown in brackets. The values sta

4、ted in each system are notexact equivalents; therefore, each system shall be used inde-pendently of the other. Combining values from the two systemsmay result in nonconformance with the standard.1.3 The text of this standard references notes that provideexplanatory material. These notes (excluding t

5、hose in tablesand figures) shall not be considered as requirements of thestandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and d

6、etermine the applica-bility of regulatory limitations prior to use. (WarningFreshhydraulic cementitious mixtures are caustic and may causechemical burns to skin and tissue upon prolonged exposure.)22. Referenced Documents2.1 ASTM Standards:3C 125 Terminology Relating to Concrete and ConcreteAggregat

7、esC 143/C 143M Test Method for Slump of Hydraulic-Cement ConcreteC 172 Practice for Sampling Freshly Mixed ConcreteC 173/C 173M Test Method for Air Content of FreshlyMixed Concrete by the Volumetric MethodC 1611/C 1611M Test Method for Slump Flow of Self-Consolidating Concrete3. Terminology3.1 Defin

8、itions:3.1.1 For definitions of terms used in this test method, referto Terminology C 125.3.2 Definitions of Terms Specific to This Standard:3.2.1 haloan observed cement paste or mortar ring thathas clearly separated from the coarse aggregate, around theoutside circumference of concrete after flowin

9、g from the slumpcone.3.2.2 J-ringan apparatus consisting of a rigid ring sup-ported on sixteen58 in. 16 mm diameter rods equally spacedon a 12 in. 300 mm diameter circle 4 in. 100 mm above aflat surface as shown in Fig. 1.3.2.3 J-ring flowthe distance of lateral flow of concreteusing the J-Ring in c

10、ombination with a slump cone.3.2.4 passing abilitythe ability of self-consolidating con-crete to flow under its own weight (without vibration) and fillcompletely all spaces within intricate formwork, containingobstacles, such as reinforcement.4. Summary of Test Method4.1 A sample of freshly mixed co

11、ncrete is placed in a slumpmold (in the upright or inverted position) that is concentricwith the J-Ring (Fig. 2). The concrete is placed in one liftwithout tamping or vibration. The mold is raised, and theconcrete is allowed to pass through J-Ring and subside (Fig. 3).The diameters of the concrete,

12、in two directions approximatelyperpendicular to each other, are measured and averaged toobtain the J-Ring flow. The test is repeated without the J-Ringto obtain the slump flow. The difference between the slumpflow and J-Ring flow is an indicator of the passing ability of theconcrete.5. Significance

13、and Use5.1 This test method provides a procedure to determine thepassing ability of self-consolidating concrete mixtures. Thedifference between the slump flow and J-Ring flow is an1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct r

14、esponsibility of SubcommitteeC09.47 on Self-Consolidating Concrete.Current edition approved June 1, 2008. Published July 2008. Originally approvedin 2006. Last previous edition approved in 2006 as C 1621/C 1621M 06.2Section on Safety Precautions, Manual of Aggregate and Concrete Testing,Annual Book

15、of ASTM Standards, Vol. 04.02.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section

16、appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.indication of the passing ability of the concrete. A differenceless than 1 in. 25 mm indicates good passing ability and adifference greater than 2 in.

17、 50 mm indicates poor passingability. The orientation of the slump cone for the J-Ring testand for the slump flow test without the J-Ring shall be thesame.5.2 This test method is applicable for laboratory use incomparing the passing ability of different concrete mixtures. Itis also applicable in the

18、 field as a quality control test.6. Apparatus6.1 J-RingThe apparatus shall consist of a steel (orequivalent nonabsorbent, rigid material) ring measuring 12 in.300 mm in diameter at the center of the ring and 1 in. 25mm in thickness, and sixteen58 in. 16 mm diameter smoothsteel rods spaced evenly aro

19、und the ring measuring 4 in. 100mm in length (see Fig. 1).6.2 MoldThe mold (slump cone) used in this test methodis as described in Test Method C 143/C 143M, except that thefoot pieces are removed when the test is performed with themold in the upright position (Procedure A).6.3 Base PlateA nonabsorbe

20、nt, rigid plate having a diam-eter of at least 36 in. 915 mm.NOTE 1Field experience has shown that base plates made from sealedor laminated plywood, rigid plastic, or steel are suitable for performingthis test.6.4 Strike Off BarAs described in Test Method C 173/C 173M.6.5 Measuring DeviceA ruler, me

21、tal roll-up measuringtape, or similar rigid or semi-rigid length measuring instrumentmarked in increments of14 in. 5 mm or less.7. Sample7.1 The sample of concrete from which test specimens aremade shall be representative of the entire batch. It shall beobtained in accordance with Practice C 172.FIG

22、. 1 J-Ring ApparatusC 1621/C 1621M 0828. Procedure8.1 Perform the test on a flat, level, and nonabsorbentsurface such as a concrete floor or a base plate. Use the baseplate in conditions where a flat, level surface is not available,such as on a construction site. When the base plate is used,position

23、 and shim the base plate so that it is fully supported andlevel. Pre-moisten the surface or base-plate with a damp towel,rag, or sponge. Rest the J-Ring on the surface or at the centerof the base plate.8.2 Filling the MoldThe operator has the option of fillingthe mold by following either Procedure A

24、 or Procedure B.8.2.1 Filling Procedure A (Upright Mold)Dampen themold, and place it on the surface or base plate with the largeropening facing down and concentric with the J-Ring. Hold themold firmly in place during filling. Fill the mold in one lift.Heap the concrete above the top of the mold.8.2.

25、2 Filling Procedure B (Inverted Mold)Dampen themold, and place it on the surface or base plate with the smalleropening facing down and concentric with the J-Ring. Supportthe mold and fill the mold in one lift. Heap the concrete abovethe top of the mold.8.3 Strike off the surface of the concrete leve

26、l with the topof the mold by a sawing motion of the strike off bar. Removeconcrete from the area surrounding the mold to precludeinterference with the movement of the flowing concrete. Raisethe mold a distance of 9 6 3 in. 230 6 75 mm in 3 6 1sbya steady vertical lift with no lateral or torsional mo

27、tion.Complete the entire procedure from start of the filling throughremoval of the mold without interruption within an elapsedtime of 212 min.8.4 Wait for the concrete to stop flowing and then measurethe largest diameter (d1) of the resulting circular flow ofconcrete. When a halo is observed in the

28、resulting circular flowof concrete, it shall be included as part of the diameter of theconcrete. Measure a second diameter (d2) of the circular flowat approximately perpendicular to the first measured diameter(d1). Measure the diameters to the nearest14 in. 5 mm.Determine the J-Ring flow in accordan

29、ce with Section 9 of thistest method.8.5 Conduct a slump flow test without the J-Ring in accor-dance with Test Method C 1611/C 1611M. Use the same fillingprocedure as used with the J-Ring. Complete the tests with andwithout the J-Ring within 6 min.9. Calculation9.1 Calculate J-Ring flow according to

30、 the following equa-tion:J2Ring flow 5d11 d2!2(1)9.2 Calculate the slump flow according to the followingequation:Slump flow 5d11 d2!2(2)9.3 Calculate the difference between slump flow and J-Ringflow to the nearest12 in. 10 mm. This number represents thepassing ability of the concrete.10. Blocking As

31、sessment10.1 Identify blocking assessment according to Table 1.11. Report11.1 Report the filling procedure (A or B) that was used.11.2 Report the J-Ring flow as the average of the twomeasured diameters to the nearest12 in. 10 mm.11.3 Report the slump flow (without the J-Ring) as theaverage of the tw

32、o measured diameters to the nearest12 in.10mm.11.4 Report the passing ability as the difference between theslump flow and J-Ring flow to the nearest12 in. 10 mm.Identify the blocking assessment.12. Precision and Bias12.1 PrecisionAn interlaboratory study of this testmethod has not been carried out.

33、In a study involving twoFIG. 2 J-Ring Setup with Inverted Mold Filled with ConcreteFIG. 3 J-Ring FlowTABLE 1 Blocking AssessmentDifference BetweenSlump Flow and J-Ring FlowBlocking Assessment0 to 1 in. 0 to 25 mm No visible blocking1 to 2 in. 25 to 50 mm Minimal to noticeable blocking2 in. 50mm Noti

34、ceable to extreme blockingC 1621/C 1621M 083operators who performed three replicate tests on 30 batches ofthe same concrete mixture during normal production at aprecast plant, the within-test standard deviation (repeatability)for passing ability was 0.23 in. 5.8 mm. The average passingability in the

35、se tests was 0.81 in. 20.5 mm for slump-flowvalues ranging from about 19 to 29 in. 480 to 740 mm.Measurements were done in the inch-pound system and the SIvalues are conversion of the inch-pound values.12.2 BiasThe procedure used in this test method has nobias since passing ability based on the J-Ri

36、ng flow is definedonly in terms of this test method.SUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this test method since the last issue,C 1621/C 1621M 06, that may impact the use of this test method. (Approved June 1, 2008)(1) Revised 1.1 to clarify the scope of

37、this test method. (2) Corrected a value in the dimension table of Fig. 1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity o

38、f any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments a

39、re invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not re

40、ceived a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C 1621/C 1621M 084