1、Designation:C174111 Designation: C1741 11aStandard Test Method forBleed Stability of Cementitious Post-Tensioning TendonGrout1This standard is issued under the fixed designation C1741; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method is designed to determine the bleed stability of freshly-mixed cementitious grout under
3、static pressure.1.2 UnitsThe values stated in SI units are to be regarded as standard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this sta
4、ndard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. (WarningFresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin andtissue upon prolonged exposure.)22. Referenced Documents2.1 ASTM Standar
5、ds:3C125 Terminology Relating to Concrete and Concrete AggregatesC938 Practice for Proportioning Grout Mixtures for Preplaced-Aggregate Concrete3. Terminology3.1 DefinitionsFor definitions of terms used in this test method, refer to Terminology C125.3.2 Definitions of Terms Specific to This Standard
6、:3.2.1 bleed stability, nof cementitious grout, resistance to bleeding.3.2.2 bleeding, nof cementitious post-tensioning tendon grout, autogenous flow of mixing water within, or its emergencefrom, newly placed grout; caused by the settlement of the solid materials within the grout and the filtering a
7、ction of strands andwires when subjected to static pressure and capillary action.3.2.3 grout, nmixture of cementitious material and water, with or without aggregate and admixtures, proportioned to producea pourable consistency without segregation of the constituents.3.2.4 post-tensioning, adjreferri
8、ng to a method of prestressing in which prestressing steel is tensioned after the concrete hasgained sufficient strength.4. Significance and Use4.1 This test method is designed to evaluate the bleed stability of a freshly-mixed grout under static pressure. It can be usedin both the laboratory to qua
9、lify grout materials and in the field as a quality control test. When used to qualify grout materials,replicate tests may be specified. It is intended that the test pressure, acceptance criteria, and number of replicate tests be set forthin the contract documents if this test method is referenced. T
10、hese values will normally vary depending on the vertical rise of thepost-tensioning tendon.NOTE 1Appendix X1 includes a reference for an example of test pressures and bleeding limits.4.2 The procedure for this test was developed by Schokker et al.4based on previous work by Schupack.51This test metho
11、d is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.41 onHydraulic Cement Grouts.Current edition approved May 1, 2011. Published June 2011. DOI: 10.1520/C1741-11Current edition approved Dec. 15, 2011. Published Ja
12、nuary 2012. Last previous edition approved in 2011 as C174111. DOI: 10.1520/C1741-11a2Section 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, or contact ASTM Customer Serv
13、ice at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4Schokker, A. J., B.D. Koester, J.E. Breen, and M. E. Kreger, “Development of High Performance Grouts for Bonded Post- Tensioned Structures,” Research Report1
14、405-2, Center for Transportation Research, October 1999.5Schupack, M. “Admixture for Controlling Bleed in Cement Grout Used in Post-Tensioning,” Precast/Prestressed Concrete Institute Journal, Nov.-Dec. 1974 , pp. 1-10.1This document is not an ASTM standard and is intended only to provide the user o
15、f an ASTM 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 pu
16、blished by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Apparatus5.1 The apparatus consists of a commercially available pressure filtration funnel, stand, pressure supply with gauge
17、, pressureregulator, valve, drip wick, and bleed water collection container as shown in Fig. 1 and Fig. 2.5.1.1 Filtration FunnelA 47-mm diameter stainless steel pressure filtration funnel with a nominal capacity of 200 mL asshown in Fig. 2. The filtration funnel shall have removable threaded caps a
18、t both ends with a stem for connection of the gas supplyand a 7.0 6 0.5 mm inside diameter stem 90 6 1 mm long for escape of water. The base of the vessel shall contain a 35 6 1mmdiameter stainless steel 45 m (No. 325) screen that supports a 47 mm diameter Type A/E borosilicate glass filter (1-m por
19、e size)as shown in Fig. 2. The screen shall be inserted with the woven side against the glass filter, and the funnel gasket shall be placedabove the glass filter as shown in Fig. 2. The glass filter shall cover the screen across the inside diameter of the bottom cap andbe located under the gasket wh
20、en under pressure. Secure the bottom cap before filling the filtration funnel with grout. The funnelis placed in the stand after it is filled.5.1.2 StandThe filtration funnel shall be attached to a stand capable of holding the funnel in the vertical position withadequate space for the bleed water co
21、llection container. The bottom stem of the filtration funnel shall be inserted into the bleedwater collection container.5.1.3 Gas SupplyAn air or other inert gas pressure supply with a pressure regulator, an in-line shutoff valve, and pressuregauge shall be firmly attached to the top stem of the fil
22、tration funnel. The pressure gauge shall be capable of reading pressures upto 700 kPa with 20 kPa graduation marks.5.1.4 Metal Drip WickA metal paper clip, or suitable thin metal wire or rod of approximately 1 mm diameter, shall be bentto direct the water squeezed out of the filtration funnel into t
23、he collection vessel.5.1.5 Bleed Water Collection ContainerThe bleed water collection container shall consist of a 10-mL transparent graduatedcylinder with 0.2-mL graduation marks.6. Sample Preparation6.1 Grout shall be mixed in accordance with the manufacturers instructions or in accordance with Pr
24、actice C938 if no otherinstructions are provided. For field quality control testing, the grout shall be mixed using the same equipment and procedure asused for the installation of the material.7. Procedure7.1 Fill the filtration funnel with freshly-mixed grout within 5 min after completion of grout
25、mixing.7.2 Screw the top stem cap on the funnel hand tight while keeping the funnel in an upright position.7.3 Place the funnel in the stand.FIG. 1 Test ApparatusC1741 11a27.4 Connect the gas supply (gas pressure at 0 kPa).7.5 Allow grout to rest in the funnel for 10 min (630 s) after grout placemen
26、t.7.6 Increase pressure to the specified pressure level (620 kPa) within 30 s.7.7 Hold at the specified pressure for 5 min (65 s) unless a longer time is specified.NOTE 2This test can be kept at the designated pressure beyond 5 min to confirm the long term bleed stability of the grout and this devia
27、tion shouldbe noted in the report.7.8 Release the pressure and tip the filtration funnel slightly to break the surface tension and allow the bleed water remainingin the exit stem to be collected as part of the bleed volume to be measured.7.9 Measure the volume of the collected bleed water to the nea
28、rest 0.2 mL at the end of the hold time.7.10 If a complete loss of pressure occurs before completion of the 5-min hold period, the test is considered invalid for thespecified pressure level.NOTE 3Loss of pressure in this test generally occurs as a “blowout” or complete loss of pressure with gas blow
29、ing out of the stem.8. Report8.1 Report the bleed volume as a percentage of the nominal sample volume as follows:% Bleeding 5bleed mL!200 mL3 100 (1)8.2 Report the pressure used for the test and the duration for which the pressure was applied.8.3 If replicate tests are specified, report each test re
30、sult individually.9. Precision and Bias9.1 PrecisionThe standard deviation obtained by one operator has been determined to be 0.03 % bleeding by volume basedon three replicate tests at 140 kPa for a grout with an average bleeding of 1.6 % by volume. For a grout tested at 220 kPa withan average bleed
31、ing of 0.6 % by volume, the standard deviation obtained by one operator has been determined to be 0.17 % basedon three replicate tests.NOTE 4An interlaboratory study will be conducted and a complete precision statement will be available by 2015.9.2 BiasNo statement on bias is being made because ther
32、e is no accepted reference material suitable for determining the biasin this test method.10. Keywords10.1 bleed stability; bleed water; bleeding; grout; post-tensioning; pressureFIG. 2 47-mm Filtration Funnel with 200 mL Nominal CapacityC1741 11a3APPENDIX(Nonmandatory Information)X1. REFERENCE FOR S
33、PECIFICATION LIMITS FOR PRESSURIZED BLEED TESTX1.1 When tested using the pressurized bleed test, the maximum percentage of permitted bleeding in grout should be specifiedin contract documents. Normally, the specification requirements for test pressure and maximum percentage bleeding will differdepen
34、ding on the vertical rise of the post-tensioning tendons being used.X1.2 The bleed limits for the test pressures based on work by Hamilton, Schokker, and Schupack6should result in grout withlittle or no bleeding for the given vertical rise. These bleed limits apply to the grout sample tested in acco
35、rdance with this testmethod for a duration of 5 min of applied pressure and do not represent the permitted amount of bleeding when the grout mixtureis used in the actual structure.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item m
36、entionedin 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 committ
37、ee 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. Your comments will receive careful consideration at a meet
38、ing 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, P
39、O 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).
40、Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).6Hamilton, H. R., A. J. Schokker, and M. Schupack, “Estimating Post-Tensioning Grout Bleed Resistance Using a Pressure- Filter Test,” Precast/Prestressed ConcreteInstitute Journal, March-April 2002, pp. 32-39.C1741 11a4
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