1、Designation: C185 15 American Association StateHighway and Transportation Officials StandardAASHTO No.: T137Standard Test Method forAir Content of Hydraulic Cement Mortar1This standard is issued under the fixed designation C185; the number immediately following the designation indicates the year ofo
2、riginal adoption or, in the case of revision, 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.This standard has been approved for use by agencies of the U.S. Departme
3、nt of Defense.1. Scope*1.1 This test method covers the determination of the aircontent of hydraulic cement mortar under the conditionshereinafter specified.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 Values in SI sha
4、ll be obtained by measurement in SIunits or by appropriate conversion, using the Rules for Con-version and Rounding in IEEE/ASTM SI 10, of measurementsmade in other units.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility
5、 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.1.5 WarningFresh hydraulic cementitious mixtures arecaustic and may cause chemical burns to skin and tissue uponprolonged exposure.22. Reference
6、d Documents2.1 ASTM Standards:3C91 Specification for Masonry CementC109/C109M Test Method for Compressive Strength ofHydraulic Cement Mortars (Using 2-in. or 50-mm CubeSpecimens)C150 Specification for Portland CementC183 Practice for Sampling and the Amount of Testing ofHydraulic CementC185 Test Met
7、hod for Air Content of Hydraulic CementMortarC230/C230M Specification for Flow Table for Use in Testsof Hydraulic CementC305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic ConsistencyC595 Specification for Blended Hydraulic CementsC778 Specification for SandC1005 Spe
8、cification for Reference Masses and Devices forDetermining Mass and Volume for Use in the PhysicalTesting of Hydraulic CementsC1157 Performance Specification for Hydraulic CementC1328 Specification for Plastic (Stucco) CementC1329 Specification for Mortar CementE438 Specification for Glasses in Labo
9、ratory ApparatusE694 Specification for Laboratory Glass Volumetric Appa-ratusIEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units (SI): The Modern Metric System3. Summary of Test Method3.1 Prepare a mortar with standard sand and the cement tobe tested, using a water content sufficien
10、t to give a requiredflow. Compact the mortar into a measure of known volume anddetermine mass. Calculate the air content from the measureddensity of the mortar, the known densities of the constituents,and the mixture proportions.4. Significance and Use4.1 The purpose of this test method is to determ
11、ine whetheror not the hydraulic cement under test meets the air-entrainingor non-air-entraining requirements of the applicable hydrauliccement specification for which the test is being made. The aircontent of concrete is influenced by many factors other than thepotential of the cement for air entrai
12、nment.5. Apparatus5.1 Flow Table, Flow Mold, and Caliper, shall conform toSpecification C230/C230M.5.2 MeasureA cylindrical measure having an inside diam-eter of 76 6 2 mm and a depth (approximately 88 mm)1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct re
13、sponsibility of Subcommittee C01.21 on Air Entrainment.Current edition approved July 1, 2015. Published July 2015. Originally approvedin 1944. Last previous edition approved in 2008 as C185 08. DOI: 10.1520/C0185-15.2Refer to the section on Safety Precautions, “Manual of Cement Testing,”Annual Book
14、of ASTM Standards, Vol 04.01.3For 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 Document Summary page onthe ASTM website.*A Summary of Changes section ap
15、pears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1adjusted by standardization with water to contain 400 6 1mLat 23.0 6 2.0C (Note 1). For the purposes of this test, thecapacity of the measure in millilit
16、res is the mass of the watercontent of the measure, in grams, divided by 0.9976, nocorrection in mass being made for the buoyant effect of air. Themeasure shall have a uniform wall thickness. The thickness ofthe wall and bottom shall not be less than 2.9 mm. The totalmass of the empty measure shall
17、not be more than 900 g. Themeasure shall be made of a metal not attacked by the cementmortar.NOTE 1Calibrate the 400 mL measure by filling with distilled waterat 23.06 2.0C to a point where the meniscus extends appreciably abovethe top of the measure, placing a clean piece of plate glass on the top
18、ofthe measure, and allowing the excess water to be squeezed out. Theabsence of air bubbles as seen through the glass ensures that the measureis completely full. Care shall be taken that the excess water is wiped fromthe sides of the container before weighing.5.3 Mixer, Bowl, and Paddle, shall confor
19、m to the apparatussection of Practice C305.5.4 StraightedgeAsteel straightedge not less than 200 mmlong and not less than 1.5 mm nor more than 3.5 mm inthickness (Note 2).NOTE 2The trowel specified in Test Method C109/C109M and thestraightedge specified in Test Method C185 may be used for this purpo
20、se,providing they comply with the planeness indicated.5.5 Trowel, having a steel blade 100 to 150 mm in length,with straight edges. The edges when placed on a plane surfaceshall not depart from straightness by more than 1 mm (Note 2).5.6 Weights and Weighing Devices, shall conform to Speci-fication
21、C1005. Evaluate the weighing device for precision andaccuracy at a total load of 2 kg.5.7 Glass GraduatesGlass graduates of 250 mL capacity,conforming to the requirements of Specifications E438 andE694.5.8 Tamper, conforming to the requirements of Test MethodC109/C109M. The tamping face of the tampe
22、r shall be flat andat right angles to the length of the tamper.5.9 Tapping Stick, a piece of hard wood having a diameterof approximately 16 mm and a length of approximately152 mm.5.10 SpoonA metal restaurant-type serving spoon not lessthan 230 mm in length and with a bowl approximately 100 mmin leng
23、th.6. Temperature and Humidity6.1 Maintain the temperature of the room and dry materialsat 23.0 6 4.0C.6.2 Condition the mixing water and the measure, if it isbeing calibrated at 23 6 2C.6.3 Maintain the relative humidity of the laboratory at notless than 50 %.7. Standard Sand7.1 Use sand conforming
24、 to the requirements of Specifica-tion C778 for 2030 sand.8. Sampling8.1 Sample the cement in accordance with Practice C183.NOTE 3Polyvinyl chloride (PVC) sample containers, upon occasion,have been found to affect the air-entraining potential of a cement sample.The same problem might be experienced
25、with containers made from otherplastics.9. Procedure9.1 BatchProportion the standard mortar using 350 gcement to 1400 g 2030 standard sand and sufficient water togive a flow of 8712 6 712 % when determined in accordancewith 9.3.NOTE 4Test Method C185 refers to hydraulic cements that complyunder Spec
26、ifications C150 and C595, and Performance SpecificationC1157. Masonry cements (see Specification C91), mortar cements (seeSpecification C1329), and plastic cements (see Specification C1328)require different sand, mass, and flow. Refer to the applicable specifica-tion.9.2 Mixing of MortarMix the mort
27、ar in accordance withPractice C305.9.3 Flow DeterminationCarefully wipe dry the flow-tabletop and place the flow mold at the center of it. Using the spoon,place a layer of mortar about 25 mm in thickness in the moldand tamp 20 times with the tamper. The tamping pressure shallbe just sufficient to en
28、sure uniform filling of the mold. Overfillthe top of the mold approximately 20 mm with mortar andtamp as specified for the first layer. Then cut off the mortar toa plane surface, flush with the top of the mold, by drawing thestraightedge with a sawing motion across the top of the mold.Wipe the flow
29、table top clean and dry, being especially carefulto remove any water from around the edge of the mold. Lift themold away from the mortar 1 min after completing the mixingoperation. Immediately drop the table 10 times in accordancewith Specification C230/C230M. The flow is the resultingincrease in av
30、erage diameter of the mortar mass, as determinedwith the calipers, measured on at least four diameters atapproximately equispaced intervals, expressed as a percentageof the original diameter. Make trial mortars with varyingpercentages of water until the specified flow is obtained. Makeeach trial wit
31、h fresh mortar.9.4 Mass per 400 mL of MortarWhen the quantity ofmixing water has been found that produces a flow of 8712 6712 %, immediately determine the mass per 400 mL of mortar,using the mortar remaining in the mixing bowl after the flowhas been determined. In the determination of the mass per40
32、0 mL, do not use the portion of the mortar used in the flowdetermination. Using the spoon, place the mortar gently intothe 400 mL measure in three equal layers. Tamp each layer20 times around the inner surface of the measure. For the finallayer of mortar, overfill the 400 mL measure approximately20
33、mm. The position of the tamper shall be that: the broad sideof the tamper is parallel to the radius and is perpendicular to theinner surface of the measure. Each layer is tamped in onecomplete revolution (rotation) with only sufficient pressure toadequately fill the measure and eliminate voids withi
34、n themortar. After the measure has been filled and tamped in theabove prescribed manner, tap the sides of the measure lightlywith the side of the tapping stick, one each at five differentC185 152points at approximately equal spacing around the outside of themeasure, in order to preclude entrapment o
35、f extraneous air(Note 5). No obvious space shall be left between the mortarand the inner surface of the measure as a result of the tampingoperation. Then cut the mortar off to a plane surface, flush withthe top of the measure, by drawing the straightedge with asawing motion across the top of the mea
36、sure, making twopasses over the entire surface, the second pass being made atright angles to the first. If, in the striking-off operation, loosesand grains cause the straightedge to ride above the top surfaceof the measure, these grains shall be removed, and theoperation repeated. Complete the entir
37、e operation of filling andstriking off the measure within 112 min. Wipe off all mortar andwater adhering to the outside of the measure. Determine themass of the measure and its contents. Subtract the mass of thecontainer, and record the mass of the mortar in grams.NOTE 5This operation may be facilit
38、ated by placing the measure ona steady flat-surfaced support of lesser diameter than the measure whilefilling and wiping.10. Calculation10.1 Calculate the air content of the mortar from thefollowing formula which is based on the batch proportionsgiven in 9.1, taking the specific gravity of portland
39、cement as3.15 and of 2030 standard sand as 2.65. When the hydrauliccement is other than portland, the appropriate value for itsspecific gravity shall be substituted for the value of 3.15 andthe formula rederived accordingly:Air content, volume% 5 100 2 W182.71P!/200014P!# (1)where:W = mass of 400 mL
40、 of mortar, g, andP = percentage of mixing water, based on mass of cementused.NOTE 6This formula is derived as follows:Air content, volume% 5 1001 2 Wa/Wc!# (2)where:Wa= actual mass per unit of volume as determined by thistest method.= W/400 g/mL, where W is the mass in grams of thespecified 400 mL
41、of mortar (9.4),Wc= theoretical mass per unit of volume, calculated on anair-free basis as follows and using the values forquantities of materials and specific gravities as givenin 9.1 and 10.1,=350114001350 3P 30.013503.15114002.651350 3P 30.011=510.01P!1.82710.01P!, andP = percentage of mixing wat
42、er, based on mass of cement.Substituting for Waand Wcwe have:Air content, volume% 5 100S1 2W40031.82710.01P510.01PDAir content, volume% 5 100 2W431.82710.01P!510.01P!Air content, volume% 5 100 2 2.5W182.71P!5000110P!Air content, volume% 5 100 2 W182.71P!200014P!10.2 Make only one determination of ai
43、r content on a batch.NOTE 7Difficulty has occasionally been experienced with this testmethod by some persons. These difficulties usually have taken the form ofvalues for air content that are abnormally high and that may be greaterthan the specified maxima in specifications for hydraulic cement. Thea
44、ir-entraining potential of the sand may be reduced by washing in thelaboratory with potable water by decantation until a clear, colorlesssupernatant liquid is obtained. In case of dispute, such freshly washedsand shall be used.11. Report11.1 When this test method is used for specific action incompli
45、ance testing, report the value for the air content to thenearest 1 %.12. Precision and Bias12.1 The single-operator, within-laboratory, standard devia-tion has been found to be 0.56 % air content throughout therange of 8 to 19 % air. Therefore, results of two properlyconducted tests by the same oper
46、ator on similar batches shouldnot differ by more than 1.6 % air.12.2 The multilaboratory standard deviation has been foundto be 1.0 % air content throughout the range from 8 to 19 % air.Therefore, results of two different laboratories on similarbatches should not differ from each other by more than
47、2.8 %air.13. Keywords13.1 air content; hydraulic cement mortarFor additional useful information on details of cement tests methods, references may be made to the “Manual of Ce-ment Testing,” which appears in the Annual Book of ASTM Standards, Vol 04.01.C185 153SUMMARY OF CHANGESCommittee C01 has ide
48、ntified the location of selected changes to this standard since the last issue (C185 08)that may impact the use of this standard. (Approved XXXX XX, 2015.)(1) Revised subsection 5.4. (2) Added Note 2 and subsection 5.5.ASTM International takes no position respecting the validity of any patent rights
49、 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 andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be address
