ASTM C1621 C1621M-2006 Standard Test Method for Passing Ability of Self-Consolidating Concrete by J-Ring.pdf

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1、Designation: C 1621/C 1621M 06Standard 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 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 of1 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 stated in

4、 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 those i

5、n 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 determi

6、ne 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 ConcreteAggregatesC 14

7、3/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 Definitions

8、: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 flowing from

9、 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 combina

10、tion 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 concrete

11、 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, in two

12、 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 and Us

13、e5.1 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 respons

14、ibility of SubcommitteeC09.47 on Self-Consolidating Concrete.Current edition approved Feb. 15, 2006. Published March 2006.2Section on Safety Precautions, Manual of Aggregate and Concrete Testing,Annual Book of ASTM Standards, Vol. 04.02.3For referenced ASTM standards, visit the ASTM website, www.ast

15、m.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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.indicatio

16、n of the passing ability of the concrete. A differenceless than 1 in. 25 mm indicates good passing ability and adifference greater than 2 in. 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

17、This test method is applicable for laboratory use incomparing the passing ability of different concrete mixtures. Itis also applicable in the 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.

18、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 around 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, ex

19、cept that thefoot pieces are removed when the test is performed with themold in the upright position (Procedure A).6.3 Base PlateA nonabsorbent, 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 plas

20、tic, 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, metal 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 conc

21、rete from which test specimens aremade shall be representative of the entire batch. It shall beobtained in accordance with Practice C 172.FIG. 1C 1621/C 1621M 0628. Procedure8.1 Perform the test on a flat, level, and nonabsorbentsurface such as a concrete floor or a base plate. Use the baseplate in

22、conditions where a flat, level surface is not available,such as on a construction site. When the base plate is used,position 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 th

23、e centerof the base plate.8.2 Filling the MoldThe operator has the option of fillingthe mold by following either Procedure A 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-R

24、ing. Hold themold firmly in place during filling. Fill the mold in one lift.Heap the concrete above the top of the mold.8.2.2 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 mo

25、ld and fill the mold in one lift. Heap the concrete abovethe top of the mold.8.3 Strike off the surface of the concrete level 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 c

26、oncrete. 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 motion.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

27、flowing and then measurethe largest diameter (d1) of the resulting circular flow ofconcrete. When a halo is observed in the 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 perpendicul

28、ar to the first measured diameter(d1). Measure the diameters to the nearest14 in. 5 mm.Determine the J-Ring flow in accordance 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

29、 the J-Ring. Complete the tests with andwithout the J-Ring within 6 min.9. Calculation9.1 Calculate J-Ring flow according to 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 slu

30、mp flow and J-Ringflow to the nearest12 in. 10 mm. This number represents thepassing ability of the concrete.10. Blocking Assessment10.1 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

31、the twomeasured diameters to the nearest12 in. 10 mm.11.3 Report the slump flow (without the J-Ring) as theaverage of the two 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 bl

32、ocking assessment.12. Precision and Bias12.1 PrecisionAn interlaboratory study of this testmethod has not been carried out. 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 FlowBloc

33、king Assessment0 to 1 in. 0 to 25 mm No visible blocking1 to 2 in. 25 to 50 mm Minimal to noticeable blocking2 in. 50mm Noticeable to extreme blockingC 1621/C 1621M 063operators who performed three replicate tests on 30 batches ofthe same concrete mixture during normal production at aprecast plant,

34、the within-test standard deviation (repeatability)for passing ability was 0.23 in. 5.8 mm. The average passingability in these 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

35、 of the inch-pound values.12.2 BiasThe procedure used in this test method has nobias since passing ability based on the J-Ring flow is definedonly in terms of this test method.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item menti

36、onedin this standard. Users of this standard are expressly advised that determination of the validity of 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 a

37、nd must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are 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

38、of theresponsible technical committee, which you may attend. If you feel that your comments have not received 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 Bo

39、x 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 064