ASTM C151 C151M-2009 Standard Test Method for Autoclave Expansion of Hydraulic Cement《水硬水泥热压膨胀的标准试验方法》.pdf

1、Designation: C 151/C 151M 09Standard Test Method forAutoclave Expansion of Hydraulic Cement1This standard is issued under the fixed designation C 151/C 151M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision

2、. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers determination of the autoclaveexpansion of hydraulic cement by means of a test on a neatcement specimen.1.

3、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 result in non-conformancewith th

4、e standard.1.3 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 determine the applica-bility of regulatory limitations prior to use.For

5、specific precau-tion statements, see the section on Safety Precautions.2. Referenced Documents2.1 ASTM Standards:2C 187 Test Method for Normal Consistency of HydraulicCementC 305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic ConsistencyC 490 Practice for Use of Appa

6、ratus for the Determinationof Length Change of Hardened Cement Paste, Mortar, andConcreteC511 Specification for Mixing Rooms, Moist Cabinets,Moist Rooms, and Water Storage Tanks Used in theTesting of Hydraulic Cements and ConcretesC 856 Practice for Petrographic Examination of HardenedConcreteC 1005

7、 Specification for Reference Masses and Devices forDetermining Mass and Volume for Use in the PhysicalTesting of Hydraulic CementsC 1157 Performance Specification for Hydraulic Cement3. Significance and Use3.1 The autoclave expansion test provides an index ofpotential delayed expansion caused by the

8、 hydration of CaO, orMgO, or both, when present in hydraulic cement.34. Interferences4.1 Pozzolans containing fine-grained quartz have beenreported to cause excessive expansion under autoclave testconditions due to alkali-silica reaction that will not occur undernormal service conditions.4When exces

9、sive expansion of pastecontaining pozzolans occurs, it is recommended that thespecimens be examined (See Practice C 856) for evidence ofalkali-silica reaction (Note 1).NOTE 1If the excessive expansion has resulted from alkali-silicareaction under autoclave conditions, the pozzolan can be evaluated f

10、oralkali reactivity using the procedure described in Performance Specifica-tion C 1157.5. Apparatus5.1 Weighing Devices and Weights, for determining themass of materials conforming to the requirements of Specifi-cation C 1005.5.2 Glass Graduates, 200 or 250-mLcapacity, and conform-ing to the require

11、ments of Practice C 490.5.3 Molds, conforming to the requirements of PracticeC 490 for test specimens used in the determination of lengthchange of cement paste.5.4 Flat Trowel, conforming to the requirements of TestMethod C 187.5.5 Autoclave, consisting of a high-pressure steam vesselprovided with a

12、 thermometer well. The autoclave shall beequipped with automatic controls and a rupture disk with abursting pressure of 2.4 MPa 350 psi 6 5 %. In locationswhere the use of a rupture disk is not permitted, the autoclaveshall be equipped with a safety valve. In addition, the autoclaveshall be equipped

13、 with a vent valve to allow the escape of airduring the early part of the heating period and to release any1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.31 on Volume Change.Current edition approved Jan. 1, 2009. Publis

14、hed January 2009. Originallyapproved in 1940. Last previous edition approved in 2005 as C 151 05.2For 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 Docum

15、ent Summary page onthe ASTM website.3Gonnerman, H. F., Lerch, W. and Whiteside, T. M. , “Investigations of theHydration Expansion Characteristics of Portland Cements,” Portland CementAssociation Research Department Bulletin 45 , pp. 1-168, 1953.4Wang, H., “Autoclave Soundness Test Mischaracterizes C

16、ement-Fly AshBlends by Introducing Alkali-Quartz Reaction,” Cement, Concrete, and Aggregates,Vol. 24, No. 2, pp. 68-72, 2002.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United S

17、tates.steam pressure remaining at the end of the cooling period. Thepressure gage shall have a nominal capacity of 4.0 MPa 600psi, a dial with a nominal diameter of 115 mm 412 in. andshall be graduated from 0 to 4.0 MPa 0 to 600 psi with scaledivisions not exceeding 0.03 MPa 5 psi. The error in the

18、gageshall not exceed 6 0.02 MPa 6 3 psi at the operatingpressure of 2 MPa 295 psi. The capacity of the heating unitshall be such that with maximum load (water plus specimens)the pressure of the saturated steam in the autoclave may beraised to a gage pressure of 2 MPa 295 psi in 45 to 75 minfrom the

19、time the heat is turned on. The automatic control shallbe capable of maintaining the gage pressure at 2 6 0.07 MPa295 6 10 psi for at least 3 h. A gage pressure of 2 6 0.07MPa 295 6 10 psi corresponds to a temperature of 216 6 2C 420 6 3 F. The autoclave shall be designed to permit thegage pressure

20、to drop from 2 MPa to less than 0.07 MPa 295psi to less than 10 psi in 112 h after the heat supply has beenshut off.5.5.1 Rupture DiskThe rupture disk shall be made of amaterial having a tensile strength that is relatively insensitiveto temperature in the range 20 to 216 C 68 to 420 F and thatis ele

21、ctrochemically compatible with the pipe leading to it andto its holder.55.6 Length ComparatorThe comparator used for measur-ing length change of specimens shall conform to the require-ments of Practice C 490.6. Temperature and Humidity6.1 Molding RoomMaintain the temperature of the mold-ing room, dr

22、y materials and mixing water, and the relativehumidity of the molding room within the limits of PracticeC 490.6.2 Moist Storage FacilitiesMaintain the temperature andhumidity of the moist storage facilities to the requirements ofSpecification C511.7. Safety Precautions7.1 The pressure gage shall hav

23、e a capacity of 4.0 MPa 600psi. A gage with too small or too large a capacity may be ahazard, since for pressure above the specified maximumworking pressure, with a smaller capacity gage, the pressuremay be off scale, and with a larger capacity gage, the arc ofmovement may be too small to invite att

24、ention. The operatorshall be sure the gage hand has not passed the maximumgraduation on the scale.7.2 Test the pressure gage for proper operation. Always usea thermometer together with the pressure gage, so as to providea means of detecting any failure of the pressure gage to operateproperly, and to

25、 indicate any unusual condition.7.3 Maintain the automatic control in proper working orderat all times.7.4 Set the safety valve to relieve the pressure at about 6 to10 % above the maximum of 2.1 MPa 305 psi specified inthis test method, that is, at about 2.3 MPa 330 psi. Unless themanufacturer has g

26、iven specific instructions as to maintenanceof the safety valve, test the valve twice each year.6Test with agage testing device, or by adjusting the automatic controls toallow the autoclave to reach a pressure of about 2.3 MPa 330psi, at which pressure the safety valve will either open or beadjusted

27、 to open. Direct the safety valve discharge away fromthe operator.NOTE 2Unexpected combinations of conditions may occur. Forexample, in one case the automatic control had failed, the safety valve hadbecome stuck, and the gage hand, which at first glance appeared to be atabout zero, had passed the ma

28、ximum graduation and had come to stop onthe wrong side of the pin. This condition of the gage was finally detectedand the pressure, then of an unknown magnitude, was released beforefailure could occur in the apparatus.7.5 Wear heavy leather work gloves to prevent burning ofthe hands when removing th

29、e top of the autoclave at the end ofthe test. Direct the vent valve away from the operator. Whenremoving the autoclave lid, tilt it so that any steam escapingfrom beneath the lid will be discharged away from the operator.Care shall be taken to avoid scalding by any liquid that mayhave been used in t

30、he autoclave well.7.6 The operator shall be made aware that for many auto-clave pressure gages the return of the gage hand to the initialrest or starting point does not necessarily indicate zero pressurewithin the autoclave; there may then still remain an appreciabledangerous pressure.8. Number of T

31、est Specimens8.1 Make at least one test specimen.9. Preparation of Specimen Molds9.1 Prepare the specimen molds in accordance with therequirements of Practice C 490 except that molds need not besealed.10. Preparation of Test Specimens10.1 Mixing Cement PastePrepare the standard batchconsisting of 65

32、0 g of cement and sufficient water to give apaste of normal consistency in accordance with the proceduredescribed in Test Method C 187. Mix this batch in accordancewith the procedure described in Practice C 305. Both a time ofsetting specimen and an autoclave bar may be made from thesame batch. If t

33、he paste to be used for time of setting is thepaste sample already used to determine normal consistency,then the autoclave bar may be prepared immediately from theremainder of the batch.10.2 Molding SpecimensImmediately following prepara-tion of the time of setting specimen or completion of mixing,m

34、old the test specimen in two approximately equal layers, eachlayer being compacted with the thumbs or forefingers bypressing the paste into the corners, around the gage studs, andalong the surface of the mold until a homogeneous specimen isobtained. Compact the top layer, cut off the paste flush wit

35、h thetop of the mold with a thin-edged trowel, and smooth thesurface with a few strokes of the flat trowel. During theoperations of mixing and molding, protect the hands withrubber gloves.5A list of suppliers of autoclave rupture disks and gaskets is maintained atASTM Headquarters.6A list of facilit

36、ies for testing autoclave safety valves is maintained at ASTMHeadquarters.C 151/C 151M 09210.3 Storage of Test SpecimensAfter filling the mold,place it in the moist closet or moist room. Store the specimensin the molds in the moist enclosure for at least 20 h; if removedfrom the molds before 24 h, t

37、hey shall be kept in the moistcloset or moist room until time of test.11. Procedure11.1 At 24 h 6 30 min after molding, remove the specimensfrom the moist atmosphere, immediately obtain a lengthcomparator reading for each specimen, and place in theautoclave at room temperature in a rack so that all

38、sides of thespecimen will be exposed to saturated steam. The autoclaveshall contain enough water, at an initial temperature of 20 to 28C 68 to 82 F, to maintain an atmosphere of saturated steamvapor during the entire test. Ordinarily 7 to 10 % of the volumeof the autoclave should be occupied by the

39、water.11.2 To permit air to escape from the autoclave during theearly portion of the heating period, leave the vent valve openuntil steam begins to escape. (WarningSee the section onSafety Precautions). Close the valve and raise the temperatureof the autoclave at a rate that will bring the gage pres

40、sure of thesteam to 2 MPa 295 psi in 45 to 75 min from the time the heatis turned on. Maintain the 2 6 0.07 MPa 295 6 10 psipressure for 3 h. At the end of the 3-h period, shut off the heatsupply and cool the autoclave at such a rate that the pressurewill be less than 0.07 MPa 10 psi at the end of 1

41、12 h. At theend of the 112-h period, slowly release any remaining pressureby partially opening the vent valve until atmospheric pressureis attained. Then open the autoclave and place the testspecimen in water at a temperature above 90 C 194 F. Coolthe water surrounding the bars at a uniform rate by

42、adding coldwater so that the temperature of the water will be lowered to 23C 74 F in 15 min. Maintain the water surrounding thespecimens at 23 C 74 F for an additional 15 min; then,remove one specimen at a time from the water, blot the pins,but not the specimen, and obtain a length comparator readin

43、g.12. Calculation12.1 Calculate the change in length of the test specimen bysubtracting the length comparator reading before autoclavingfrom that after autoclaving, and report as percent of effectivegage length to the nearest 0.01 %. Report the percentage ofincrease in length as the autoclave expans

44、ion. Indicate adecrease in length by a minus sign prefixed to the percentvalue.13. Precision and Bias13.1 PrecisionThe single-operator (within-laboratory)standard deviation has been found to be 0.024 % throughoutthe range of 0.11 % to 0.94 % expansions. Therefore, results oftwo properly conducted te

45、sts by the same operator for expan-sions of similar batches should not differ from each other bymore than 0.07 % expansion. The multi-laboratory (betweenlaboratory) standard deviation has been found to be 0.030 %throughout the range of 0.11 % to 0.94 % expansions. There-fore, results of two properly

46、 conducted tests from two differentlaboratories for expansions of similar batches should not differfrom each other by more than 0.09 % expansion.13.2 BiasSince there is no accepted reference materialsuitable for determining bias, bias has not been determined.14. Keywords14.1 autoclave; autoclave exp

47、ansion; expansion; hydrauliccement; soundnessFor additional useful information on details of cement test methods, reference may be made to the “Manual of CementTesting,” which appears in the Annual Book of ASTM Standards, Vol 04.01.SUMMARY OF CHANGESCommittee C01 has identified the location of selec

48、ted changes to this test method since the last issue,C 151 05, that may impact the use of this test method. (Approved January 1, 2009)(1) Revised the standard as a combined units standard.ASTM International takes no position respecting the validity of any patent rights asserted in connection with an

49、y 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 andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be address