ASTM C1621C1621M-17 Standard Test Method for Passing Ability of Self-Consolidating Concrete by J-Ring.pdf

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1、Designation: C1621/C1621M 17Standard Test Method forPassing Ability of Self-Consolidating Concrete by J-Ring1This standard is issued under the fixed designation C1621/C1621M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year

2、 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 (SCC) by using theJ-Ri

3、ng in combination with a mold.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may

4、result in non-conformancewith the standard.1.3 The text of this standard references notes and footnotesthat provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be consideredas requirements of the standard.1.4 This standard does not purport to addr

5、ess 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 determine the applica-bility of regulatory limitations prior to use. (WarningFreshhydraulic cementitious mixtures are caustic

6、 and may causechemical burns to skin and tissue upon prolonged exposure.2)1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Re

7、com-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3C125 Terminology Relating to Concrete and Concrete Ag-gregatesC143/C143M Test Method for Slump of Hydraulic-CementConcreteC172 Practice for Sampling Freshly Mix

8、ed ConcreteC173/C173M Test Method for Air Content of Freshly MixedConcrete by the Volumetric MethodC1611/C1611M Test Method for Slump Flow of Self-Consolidating ConcreteC1758/C1758M Practice for Fabricating Test Specimenswith Self-Consolidating Concrete3. Terminology3.1 Definitions:3.1.1 For definit

9、ions of terms used in this test method, referto Terminology C125.3.2 Definitions of Terms Specific to This Standard:3.2.1 halo, nan observed cement paste or mortar ring thathas clearly separated from the coarse aggregate, around theoutside circumference of concrete after flowing from the mold.3.2.2

10、J-ring, nan apparatus consisting of a rigid ringsupported on sixteen 16 mm 58 in. diameter rods equallyspaced on a 300 mm 12 in. diameter circle 100 mm 4 in.above a flat surface as shown in Fig. 1.3.2.3 J-ring flow, nthe distance of lateral flow of concreteusing the J-Ring in combination with a mold

11、.3.2.4 passing ability, nthe ability of self-consolidatingconcrete to flow under its own weight (without vibration) andfill completely all spaces within intricate formwork, containingobstacles, such as reinforcement.4. Summary of Test Method4.1 A sample of freshly mixed concrete is placed in a mold,

12、either in the upright or inverted position, that is concentric withthe J-Ring (Fig. 2). The concrete is placed in one lift withouttamping or vibration. The mold is raised, and the concrete isallowed to spread through the J-Ring (Fig. 3). After spreadingceases, two diameters of the concrete mass are

13、measured inapproximately orthogonal directions. J-Ring flow is the aver-age of the two diameters. The test is repeated without theJ-Ring to obtain the slump flow. The difference between theslump flow and J-Ring flow is an indicator of the passingability of the concrete.1This test method is under the

14、 jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.47 on Self-Consolidating Concrete.Current edition approved Aug. 1, 2017. Published August 2017. Originallyapproved in 2006. Last previous edition approved in 2014 as C1621/C1621

15、M 14.DOI: 10.1520/C1621_C1621M-17.2Section 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.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandar

16、ds volume information, refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was dev

17、eloped in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15. Significance a

18、nd Use5.1 This test method provides a procedure to determine thepassing ability of self-consolidating concrete. This test methodis applicable for laboratory use in comparing the passing abilityof different concrete mixtures. It is also applicable in the fieldas a quality control test.5.2 The differe

19、nce between the slump flow and J-Ring flowis an indication of the passing ability of the concrete. Adifference less than 25 mm 1 in. indicates good passingability and a difference greater than 50 mm 2 in. indicatespoor passing ability. The orientation of the mold for the J-Ringtest and for the slump

20、 flow test without the J-Ring shall be thesame.5.3 This test method is limited to self-consolidating con-crete with nominal maximum size of aggregate of up to 25 mm1 in.6. Apparatus6.1 J-RingThe apparatus shall consist of a steel (orequivalent nonabsorbent, rigid material) ring measuring300 mm 12 in

21、. in diameter at the center of the ring and25 mm 1 in. in thickness, and sixteen 16 mm 58 in. diametersmooth steel rods spaced evenly around the ring measuring 100mm 4 in. in length (see Fig. 1).6.2 MoldThe mold used in this test method shall conformto that described in Test Method C143/C143M, excep

22、t that thefoot pieces are removed when the test is performed with themold in the upright position (Procedure A).6.3 Base PlateA nonabsorbent, smooth, rigid plate havinga minimum diameter of 915 mm 36 in.NOTE 1Field experience has shown that base plates made from sealedor laminated plywood, rigid pla

23、stic, or steel are suitable for performingthis test.FIG. 1 J-Ring ApparatusC1621/C1621M 1726.4 Strike-off BarAs described in Test Method C173/C173M.6.5 Measuring DeviceA ruler, metal roll-up measuringtape, or similar rigid or semi-rigid measuring instrumentmarked in increments of 5 mm 14 in. or less

24、.6.6 Sample ReceptacleA pan or wheelbarrow that iswater-tight, has a nonabsorbent surface, and is large enough toallow both remixing of the entire sample and retain a volumeof concrete sufficient to fill the mold.6.7 Other ToolsItems such as shovels and scoops capableof remixing the concrete in the

25、sample receptacle, filling thepouring vessel, or both.7. Sample7.1 Obtain a sample of freshly-mixed self-consolidatingconcrete in accordance with Practice C172 and place it in thesample receptacle.8. Procedure8.1 Perform this test on a flat, level, nonabsorbent worksurface such as a concrete floor o

26、r base plate. Use a base platein conditions where a flat, level surface is not available, such ason a construction site. When the base plate is used, position andshim the base plate so that it is fully supported. Dampen thework surface, removing any standing water. Do not subject thework surface or

27、mold to vibration or disturbance.8.1.1 When performing the slump flow test for a given studyor project, do not change the base plate type for the duration ofthe study or project.8.1.2 Place the J-Ring on the work surface or at the centerof the base plate.8.2 Remixing of Sample. Remix the sample, obt

28、ained inaccordance with 7.1, in the sample receptacle using a shovel orscoop so that the concrete is homogeneous.8.3 Filling the MoldFill the mold by following eitherProcedure A or Procedure B.8.3.1 Filling Procedure A (Upright Mold)Dampen theinterior of the mold and place it on the work surface or

29、baseplate with the larger opening facing down and concentric withthe J-Ring. Hold the mold firmly in place during filling.8.3.2 Filling Procedure B (Inverted Mold)Dampen theinterior of the mold and place it on the work surface or baseplate with the smaller opening facing down and concentric withthe

30、J-Ring (see Note 2).NOTE 2As a precaution, when filling the mold in the invertedposition, the mold may be supported to prevent accidental movement ortipping. Experienced users of this test method have found that it is notnecessary to support the mold.8.3.3 Fill the mold with SCC in accordance with t

31、heprocedure in Practice C1758/C1758M.8.4 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 base of the mold topreclude interference with the movement of the flowingconcrete. Remove the mold from

32、 the concrete by raising itvertically. Raise the mold a distance of 225 6 75 mm 9 63 in. in 3 6 1 s by a steady upward lift with no lateral ortorsional motion. Complete the entire test from the start offilling through removal of the mold without interruption withinan elapsed time of 212 min.8.5 Wait

33、 for the concrete to stop flowing and then measurethe largest diameter (j1) of the resulting circular spread ofconcrete. When a halo is observed in the resulting circularspread of concrete, it shall be included as part of the diameterof the concrete. Measure a second diameter (j2) of the circularspr

34、ead at an angle approximately perpendicular to the firstmeasured diameter (j1). Measure the diameters to the nearest5mm14 in. Determine the J-Ring flow in accordance withSection 9.8.6 If the measurement of the two diameters differs by morethan 50 mm 2 in., the test is invalid and shall be repeated.8

35、.7 Conduct a slump flow test without the J-Ring in accor-dance with Test Method C1611/C1611M. 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 the following equa-tion:FIG. 2 J-Ring S

36、etup with Inverted Mold Filled with ConcreteFIG. 3 J-Ring FlowC1621/C1621M 173J 2 Ring flow 5j11j2!2(1)where:j1= the largest diameter of the circular spread of the con-crete from the J-Ring test, andj2= the circular spread of the concrete at an angle approxi-mately perpendicular to j1.9.2 Calculate

37、the slump flow according to the followingequation:Slump flow 5d11d2!2(2)where:d1= the largest diameter of the circular spread of theconcrete from the slump flow test, andd2= the circular spread of the concrete at an angle approxi-mately perpendicular to d1.9.3 Calculate the difference between slump

38、flow and J-Ringflow to the nearest 10 mm 12 in. 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) used.11.2 Report the J-Ring flow to the nearest 10 mm 12 in.11.

39、3 Report the slump flow (without the J-Ring) to thenearest 10 mm 12 in.11.4 Report the passing ability as the difference between theslump flow and J-Ring flow to the nearest 10 mm 12 in.Identify the blocking assessment.12. Precision and Bias12.1 PrecisionAn interlaboratory study of this test methodh

40、as not been carried out. In a study involving two operatorswho performed three replicate tests on 30 batches of the sameconcrete mixture during normal production at a precast plant,the within-test standard deviation (repeatability) for passingability was 5.8 mm 0.23 in. The average passing ability i

41、nthese tests was 20.5 mm 0.81 in. for slump-flow valuesranging from about 480 to 740 mm 19 to 29 in. Measure-ments were done in the inch-pound system and the SI valuesare conversion of the inch-pound values.12.2 BiasThe procedure used in this test method has nobias since passing ability based on the

42、 J-Ring flow is definedonly in terms of this test method.13. Keywords13.1 halo; j-ring; j-ring flow; passing ability self-consolidating concrete; slump flow; spreadSUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this standard since the last issue(C1621/C1621M 14) t

43、hat may impact the use of this standard. (Approved Aug. 1, 2017.)(1) Added Practice C1758/C1758M to list of referenced docu-ments (Section 2).(2) Removed previous 6.7 and Note 2.(3) Removed previous 8.3.3 through 8.3.5.(4) Added new 8.3.3.ASTM International takes no position respecting the validity

44、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 of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject t

45、o 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 are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters.

46、 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 received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is

47、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 serviceast

48、m.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 1 Blocking AssessmentDifference BetweenSlump Flow and J-Ring FlowBlocking Assessment0 to 25 mm 0 to 1 in. No visible blocking25 to 50 mm 1 to 2 in. Minimal to noticeable blocking50 mm 2 in. Noticeable to extreme blockingC1621/C1621M 174