ASTM C1621 C1621M-2017 Standard Test Method for Passing Ability of Self-Consolidating Concrete by J-Ring《利用J环测定自密实混凝土通过能力的标准试验方法》.pdf

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1、Designation: C1621/C1621M 14C1621/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 rev

2、ision, the 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 passing ability of self-consolidating concrete (SCC)

3、by using the J-Ring incombination with a mold.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from t

4、hetwo systems may result in non-conformance with the standard.1.3 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be considered as requirements of the standard.1.4 This standard doe

5、s not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. (WarningFresh hydraulic cementitious

6、mixtures are caustic and may cause chemical burns to skin andtissue upon prolonged exposure.2)1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standa

7、rds, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3C125 Terminology Relating to Concrete and Concrete AggregatesC143/C143M Test Method for Slump of Hydraulic-Cement ConcreteC172 Practice for Sam

8、pling Freshly Mixed ConcreteC173/C173M Test Method for Air Content of Freshly Mixed Concrete by the Volumetric MethodC1611/C1611M Test Method for Slump Flow of Self-Consolidating ConcreteC1758/C1758M Practice for Fabricating Test Specimens with Self-Consolidating Concrete3. Terminology3.1 Definition

9、s:3.1.1 For definitions of terms used in this test method, refer to Terminology C125.3.2 Definitions of Terms Specific to This Standard:3.2.1 halo, nan observed cement paste or mortar ring that has clearly separated from the coarse aggregate, around the outsidecircumference of concrete after flowing

10、 from the mold.3.2.2 J-ring, nan apparatus consisting of a rigid ring supported on sixteen 16 mm 58 in. diameter rods equally spaced ona 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 concrete using the J-Ring in

11、 combination with a mold.1 This test method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.47 onSelf-Consolidating Concrete.Current edition approved April 1, 2014Aug. 1, 2017. Published May 2014August 2017. Ori

12、ginally approved in 2006. Last previous edition approved in 20092014 asC1621/C1621M 09b.C1621/C1621M 14. DOI: 10.1520/C1621_C1621M-14.10.1520/C1621_C1621M-17.2 Section on Safety Precautions, Manual of Aggregate and Concrete Testing, Annual Book of ASTM Standards, Vol 04.02.3 For referencedASTM stand

13、ards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an AS

14、TM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published

15、 by ASTM is to be considered the official document.*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 States13.2.4 passing ability, nthe ability of self-consolidating concrete to

16、flow under its own weight (without vibration) and fillcompletely all spaces within intricate formwork, containing obstacles, such as reinforcement.4. Summary of Test Method4.1 A sample of freshly mixed concrete is placed in a mold, either in the upright or inverted position, that is concentric witht

17、he J-Ring (Fig. 2). The concrete is placed in one lift without tamping or vibration. The mold is raised, and the concrete is allowedto spread through the J-Ring (Fig. 3). After spreading ceases, two diameters of the concrete mass are measured in approximatelyorthogonal directions. J-Ring flow is the

18、 average of the two diameters. The test is repeated without the J-Ring to obtain the slumpflow. The difference between the slump flow and J-Ring flow is an indicator of the passing ability of the concrete.5. Significance and Use5.1 This test method provides a procedure to determine the passing abili

19、ty of self-consolidating concrete. This test method isapplicable for laboratory use in comparing the passing ability of different concrete mixtures. It is also applicable in the field as aquality control test.5.2 The difference between the slump flow and J-Ring flow is an indication of the passing a

20、bility of the concrete. A differenceless than 25 mm 1 in. indicates good passing ability and a difference greater than 50 mm 2 in. indicates poor passing ability.The orientation of the mold for the J-Ring test and for the slump flow test without the J-Ring shall be the same.5.3 This test method is l

21、imited to self-consolidating concrete with nominal maximum size of aggregate of up to 25 mm 1 in.FIG. 1 J-Ring ApparatusC1621/C1621M 1726. Apparatus6.1 J-RingThe apparatus shall consist of a steel (or equivalent nonabsorbent, rigid material) ring measuring 300 mm 300 mm12 in. in diameter at the cent

22、er of the ring and 25 mm 1 in. 25 mm 1 in. in thickness, and sixteen 16 mm 58 in. diametersmooth steel rods spaced evenly around the ring measuring 100 mm 4 in. 4 in. in length (see Fig. 1).6.2 MoldThe mold used in this test method shall conform to that described in Test Method C143/C143M, except th

23、at the footpieces are removed when the test is performed with the mold in the upright position (Procedure A).6.3 Base PlateA nonabsorbent, smooth, rigid plate having a minimum diameter of 915 mm 36 in.NOTE 1Field experience has shown that base plates made from sealed or laminated plywood, rigid plas

24、tic, or steel are suitable for performing thistest.6.4 Strike-off BarAs described in Test Method C173/C173M.6.5 Measuring DeviceA ruler, metal roll-up measuring tape, or similar rigid or semi-rigid measuring instrument marked inincrements of 5 mm 14 in. or less.6.6 Sample ReceptacleApan or wheelbarr

25、ow that is water-tight, has a nonabsorbent surface, and is large enough to allow bothremixing of the entire sample and retain a volume of concrete sufficient to fill the mold.6.7 Pouring Vessel for SCCA water-tight container having a volume such that concrete is not spilled during placement in themo

26、ld.NOTE 2A pouring vessel with a pouring lip is useful in reducing the probability of concrete spilling while filling the mold.6.7 Other ToolsItems such as shovels and scoops capable of remixing the concrete in the sample receptacle, filling the pouringvessel, or both.FIG. 2 J-Ring Setup with Invert

27、ed Mold Filled with ConcreteFIG. 3 J-Ring FlowC1621/C1621M 1737. Sample7.1 Obtain a sample of freshly-mixed self-consolidating concrete in accordance with Practice C172 and place it in the samplereceptacle.8. Procedure8.1 Perform this test on a flat, level, nonabsorbent work surface such as a concre

28、te floor or base plate. Use a base plate inconditions where a flat, level surface is not available, such as on a construction site. When the base plate is used, position and shimthe base plate so that it is fully supported. Dampen the work surface, removing any standing water. Do not subject the wor

29、k surfaceor mold to vibration or disturbance.8.1.1 When performing the slump flow test for a given study or 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 center of the base plate.8.2 Remixing of Sample. Remix t

30、he sample, obtained in accordance with 7.1, in the sample receptacle using a shovel or scoopso that the concrete is homogeneous.8.3 Filling the MoldFill the mold by following either Procedure A or Procedure B.8.3.1 Filling Procedure A (Upright Mold)Dampen the interior of the mold and place it on the

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

32、concentric with the J-Ring (see Note 32).NOTE 2As a precaution, when filling the mold in the inverted position, the mold may be supported to prevent accidental movement or tipping.Experienced users of this test method have found that it is not necessary to support the mold.8.3.3 Fill Pouring VesselI

33、mmediately fill the pouring vessel with a portion of SCC from the sample receptacle, eitherFill themold with SCC in accordance with the procedure in Practice C1758/C1758Mby passing the pouring vessel through the concreteor by scooping concrete into the vessel. .8.3.4 Filling ProcedureImmediately fil

34、l the mold with SCC by tilting the pouring vessel. Position the lowest point on the rimof the pouring vessel no more than 125 mm 5 in. above the top of the mold. Ensure an even distribution of concrete, withoutrodding the concrete or tapping the sides of the mold, while filling the mold.8.3.5 If nec

35、essary, repeat the procedures in 8.3.3 and 8.3.4 until the mold is filled slightly above its rim.8.4 Strike off the surface of the concrete level with the top of the mold by a sawing motion of the strike-off bar. Remove concretefrom the area surrounding the base of the mold to preclude interference

36、with the movement of the flowing concrete. Remove themold from the concrete by raising it vertically. Raise the mold a distance of 225 6 75 mm 9 6 3 in. 3 in. in 3 6 1 s by a steadyupward lift with no lateral or torsional motion. Complete the entire test from the start of filling through removal of

37、the mold withoutinterruption within an elapsed time of 2 12 min.8.5 Wait for the concrete to stop flowing and then measure the largest diameter (j1) of the resulting circular spread of concrete.When a halo is observed in the resulting circular spread of concrete, it shall be included as part of the

38、diameter of the concrete.Measure a second diameter (j2) of the circular spread at an angle approximately perpendicular to the first measured diameter (j1).Measure the diameters to the nearest 5 mm 5 mm 14 in. Determine the J-Ring flow in accordance with Section 9.8.6 If the measurement of the two di

39、ameters differs by more than 50 mm 2 in., the test is invalid and shall be repeated.8.7 Conduct a slump flow test without the J-Ring in accordance with Test Method C1611/C1611M. Use the same fillingprocedure as used with the J-Ring. Complete the tests with and without the J-Ring within 6 min.9. Calc

40、ulation9.1 Calculate J-Ring flow according to the following equation:J2Ring flow5j11j2!2 (1)where:j1 = the largest diameter of the circular spread of the concrete from the J-Ring test, andj2 = the circular spread of the concrete at an angle approximately perpendicular to j1.9.2 Calculate the slump f

41、low according to the following equation:Slump flow5d11d2!2 (2)where:d1 = the largest diameter of the circular spread of the concrete from the slump flow test, andC1621/C1621M 174d2 = the circular spread of the concrete at an angle approximately perpendicular to d1.9.3 Calculate the difference betwee

42、n slump flow and J-Ring flow 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

43、12 in.11.3 Report the slump flow (without the J-Ring) to the nearest 10 mm 12 in.11.4 Report the passing ability as the difference between the slump flow and J-Ring flow to the nearest 10 mm 12 in. Identifythe blocking assessment.12. Precision and Bias12.1 PrecisionAn interlaboratory study of this t

44、est method has not been carried out. In a study involving two operators whoperformed three replicate tests on 30 batches of the same concrete mixture during normal production at a precast plant, thewithin-test standard deviation (repeatability) for passing ability was 5.8 mm 0.23 in. The average pas

45、sing ability in these testswas 20.5 mm 0.81 in. for slump-flow values ranging from about 480 to 740 mm 19 to 29 in. Measurements were done in theinch-pound system and the SI values are conversion of the inch-pound values.12.2 BiasThe procedure used in this test method has no bias since passing abili

46、ty based on the J-Ring flow is defined onlyin 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(C16

47、21/C1621M 09bC1621/C1621M 14) that may impact the use of this standard. (Approved Aug. 1,2017April 1, 2014.).)(1) Added new 6.6,Practice C1758/C1758M 6.7 with Note, and 6.8.to list of referenced documents (Section 2).(2) Revised 7.1.Removed previous 6.7 and Note 2.(3) Revised Section 8 .Removed prev

48、ious 8.3.3 through 8.3.5.(4) Added new 8.2.8.3.3.(5) Removed old Note 3.TABLE 1 Blocking AssessmentDifference BetweenSlump Flow and J-Ring Flow Blocking 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 blockingC

49、1621/C1621M 175ASTM 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 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 and must be reviewed every five years