1、Designation: C 204 07American Association StateHighway and Transportation Officials StandardAASHTO No.: T 153Standard Test Methods forFineness of Hydraulic Cement by Air-PermeabilityApparatus1This standard is issued under the fixed designation C 204; the number immediately following the designation
2、indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers determinatio
3、n of the fineness ofhydraulic cement, using the Blaine air-permeability apparatus,in terms of the specific surface expressed as total surface areain square centimetres per gram, or square metres per kilogram,of cement. Two test methods are given: Test Method A is theReference Test Method using the m
4、anually operated standardBlaine apparatus, while Test Method B permits the use ofautomated apparatus that has in accordance with the qualifica-tion requirements of this test method demonstrated acceptableperformance. Although the test method may be, and has been,used for the determination of the mea
5、sures of fineness ofvarious other materials, it should be understood that, ingeneral, relative rather than absolute fineness values areobtained.1.1.1 This test method is known to work well for portlandcements. However, the user should exercise judgement indetermining its suitability with regard to f
6、ineness measure-ments of cements with densities, or porosities that differ fromthose assigned to Standard Reference Material No. 114.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with it
7、s 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.2. Referenced Documents2.1 ASTM Standards:2A 582/A 582M Specification for Free-Machining StainlessSteel BarsC 670
8、Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsE 832 Specification for Laboratory Filter Papers2.2 Other Document:No. 114 National Institute of Standards and TechnologyStandard Reference Material3BS 4359: 1971 British Standard Method for the Determina-
9、tion of Specific Surface of Powders: Part 2: Air Perme-ability Methods4TEST METHOD A: REFERENCE METHOD3. Apparatus3.1 Nature of ApparatusThe Blaine air-permeability ap-paratus consists essentially of a means of drawing a definitequantity of air through a prepared bed of cement of definiteporosity. T
10、he number and size of the pores in a prepared bed ofdefinite porosity is a function of the size of the particles anddetermines the rate of airflow through the bed. The apparatus,illustrated in Fig. 1, shall consist specifically of the partsdescribed in 3.2-3.8.3.2 Permeability CellThe permeability c
11、ell shall consistof a rigid cylinder 12.70 6 0.10 mm in inside diameter,constructed of austenitic stainless steel. The interior of the cellshall have a finish of 0.81 m (32 in.). The top of the cell shallbe at right angles to the principal axis of the cell. The lowerportion of the cell must be able
12、to form an airtight fit with theupper end of the manometer, so that there is no air leakagebetween the contacting surfaces. A ledge12 to 1 mm in widthshall be an integral part of the cell or be firmly fixed in the cell55 6 10 mm from the top of the cell for support of theperforated metal disk. The t
13、op of the permeability cell shall befitted with a protruding collar to facilitate the removal of thecell from the manometer.NOTE 1Specification A 582/A 582M Type 303 stainless steel (UNSdesignation S30300) has been found to be suitable for the construction ofthe permeability cell and the plunger.3.3
14、 DiskThe disk shall be constructed of noncorrodingmetal and shall be 0.9 6 0.1 mm in thickness, perforated with30 to 40 holes 1 mm in diameter equally distributed over itsarea. The disk shall fit the inside of the cell snugly. The center1This test method is under the jurisdiction of ASTM Committee C
15、01 on Cementand is the direct responsibility of Subcommittee C01.25 on Fineness.Current edition approved Aug. 1, 2007. Published September 2007. Originallyapproved in 1946. Last previous edition approved in 2005 as C 204 05.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcont
16、act ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from National Institute of Standards and Technology (NIST), 100Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.n
17、ist.gov.4Available from British Standards Institute (BSI), 389 Chiswick High Rd.,London W4 4AL, U.K., http:/www.bsi-.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 States.po
18、rtion of one side of the disk shall be marked or inscribed ina legible manner so as to permit the operator always to placethat side downwards when inserting it into the cell. Themarking or inscription shall not extend into any of the holes,nor touch their peripheries, nor extend into that area of th
19、e diskthat rests on the cell ledge.3.4 PlungerThe plunger shall be constructed of austeniticstainless steel and shall fit into the cell with a clearance of notmore than 0.1 mm. The bottom of the plunger shall sharplymeet the lateral surfaces and shall be at right angles to theprincipal axis. An air
20、vent shall be provided by means of a flat3.0 6 0.3 mm wide on one side of the plunger. The top of theplunger shall be provided with a collar such that when theplunger is placed in the cell and the collar brought in contactwith the top of the cell, the distance between the bottom of theplunger and th
21、e top of the perforated disk shall be 15 6 1 mm.3.5 Filter PaperThe filter paper shall be medium reten-tive, corresponding to Type 1, Grade B, in accordance withSpecification E 832. The filter paper disks shall be circular,with smooth edges, and shall have the same diameter (Note 2)as the inside of
22、the cell.NOTE 2Filter paper disks that are too small may leave part of thesample adhering to the inner wall of the cell above the top disk. When toolarge in diameter, the disks have a tendency to buckle and cause erraticresults.3.6 ManometerThe U-tube manometer shall be con-structed according to the
23、 design indicated in Fig. 1, usingnominal 9-mm outside diameter, standard-wall, glass tubing.The top of one arm of the manometer shall form an airtightconnection with the permeability cell. The manometer armconnected to the permeability cell shall have a midpoint lineetched around the tube at 125 to
24、 145 mm below the top sideoutlet and also others at distances of 15 6 1 mm, 70 6 1 mm,and 110 6 1 mm above that line.Aside outlet shall be providedat 250 to 305 mm above the bottom of the manometer for useFIG. 1 Blaine Air-Permeability ApparatusC204072in the evacuation of the manometer arm connected
25、 to thepermeability cell. A positive airtight valve or clamp shall beprovided on the side outlet not more than 50 mm from themanometer arm. The manometer shall be mounted firmly andin such a manner that the arms are vertical.3.7 Manometer LiquidThe manometer shall be filled tothe midpoint line with
26、a nonvolatile, nonhygroscopic liquid oflow viscosity and density, such as dibutyl phthalate (dibutyl1,2-benzene-dicarboxylate) or a light grade of mineral oil. Thefluid shall be free of debris.3.8 TimerThe timer shall have a positive starting andstopping mechanism and shall be capable of being read
27、to thenearest 0.5 s or less. The timer shall be accurate to 0.5 s or lessfor time intervals up to 60 s, and to 1 % or less for timeintervals of 60 to 300 s.4. Calibration of Apparatus4.1 SampleThe calibration of the air permeability appa-ratus shall be made using the current lot of NIST StandardRefe
28、rence Material No. 114. The sample shall be at roomtemperature when tested.4.2 Bulk Volume of Compacted Bed of PowderDeterminethe bulk volume of the compacted bed of powder by themercury displacement method as follows:4.2.1 Place two filter paper disks in the permeability cell,pressing down the edge
29、s, using a rod having a diameter slightlysmaller than that of the cell, until the filter disks are flat on theperforated metal disk; then fill the cell with mercury, ACSreagent grade or better, removing any air bubbles adhering tothe wall of the cell. Use tongs when handling the cell. If the cellis
30、made of material that will amalgamate with mercury, theinterior of the cell shall be protected by a very thin film of oiljust prior to adding the mercury. Level the mercury with the topof the cell by lightly pressing a small glass plate against themercury surface until the glass is flush to the surf
31、ace of themercury and rim of the cell, being sure that no bubble or voidexists between the mercury surface and the glass plate.Remove the mercury from the cell and measure and record themass of the mercury. Remove one of the filter disks from thecell. Using a trial quantity of 2.80 g of cement (Note
32、 3)compress the cement (Note 4) in accordance with 4.5 with onefilter disk above and one below the sample. Into the unfilledspace at the top of the cell, add mercury, remove entrapped air,and level off the top as before. Remove the mercury from thecell and measure and record the mass of the mercury.
33、4.2.2 Calculate the bulk volume occupied by the cement tothe nearest 0.005 cm3as follows:V 5 WA2 WB!/D (1)where:V = bulk volume of cement, cm3,WA= grams of mercury required to fill the cell, no cementbeing in the cell,WB= grams of mercury required to fill the portion of thecell not occupied by the p
34、repared bed of cement inthe cell, andD = density of mercury at the temperature of test,Mg/m3(see Table 1).4.2.3 Make at least two determinations of bulk volume ofcement, using separate compactions for each determination.The bulk volume value used for subsequent calculations shallbe the average of tw
35、o values agreeing within 60.005 cm3.Note the temperature in the vicinity of the cell and record at thebeginning and end of the determination.NOTE 3It is not necessary to use the standard sample for the bulkvolume determination.NOTE 4The prepared bed of cement shall be firm. If too loose or if thecem
36、ent cannot be compressed to the desired volume, adjust the trialquantity of cement used.4.3 Preparation of SampleEnclose the contents of a vialof the standard cement sample in a jar, approximately 120 cm3(4 oz), and shake vigorously for 2 min to fluff the cement andbreak up lumps or agglomerates. Al
37、low the jar to standunopened for a further 2 min, then remove the lid and stirgently to distribute throughout the sample the fine fraction thathas settled on the surface after fluffing.4.4 Mass of SampleThe mass of the standard sample usedfor the calibration test shall be that required to produce a
38、bedof cement having a porosity of 0.500 6 0.005, and shall becalculated as follows:W 5rV1 2e! (2)where:W = grams of sample required,r = density of test sample (for portland cement a value of3.15 Mg/m3or 3.15 g/cm3shall be used),V = bulk volume of bed of cement, cm3, as determined inaccordance with 4
39、.2, ande = desired porosity of bed of cement (0.500 6 0.005)(Note 5).NOTE 5The porosity is the ratio of volume of voids in a bed of cementto the total or bulk volume of the bed, V.4.5 Preparation of Bed of CementSeat the perforated diskon the ledge in the permeability cell, inscribed or marked faced
40、own. Place a filter paper disk on the metal disk and press theedges down with a rod having a diameter slightly smaller thanthat of the cell. Measure the mass to the nearest 0.001 g thequantity of cement determined in accordance with 4.4 andplace in the cell. Tap the side of the cell lightly in order
41、 to levelthe bed of cement. Place a filter paper disk on top of the cementand compress the cement with the plunger until the plungercollar is in contact with the top of the cell. Slowly withdraw theTABLE 1 Density of Mercury, Viscosity of Air (h), and = h atGiven TemperaturesRoomTemperature, CDensit
42、y ofMercury,Mg/m3Viscosity of Air, hPas=h18 13.55 17.98 4.2420 13.55 18.08 4.2522 13.54 18.18 4.2624 13.54 18.28 4.2826 13.53 18.37 4.2928 13.53 18.47 4.3030 13.52 18.57 4.3132 13.52 18.67 4.3234 13.51 18.76 4.33C204073plunger a short distance, rotate about 90, repress, and thenslowly withdraw. Use
43、of fresh paper filter disks is required foreach determination.4.6 Permeability Test:4.6.1 Attach the permeability cell to the manometer tube,making certain that an airtight connection is obtained (Note 6)and taking care not to jar or disturb the prepared bed of cement.4.6.2 Slowly evacuate the air i
44、n the one arm of the manom-eter U-tube until the liquid reaches the top mark, and then closethe valve tightly. Start the timer when the bottom of themeniscus of the manometer liquid reaches the second (next tothe top) mark and stop when the bottom of the meniscus ofliquid reaches the third (next to
45、the bottom) mark. Note thetime interval measured and record in seconds. Note thetemperature of test and record in degrees Celsius.4.6.3 In the calibration of the instrument, make at least threedeterminations of the time of flow on each of three separatelyprepared beds of the standard sample (Note 7)
46、. The calibrationshall be made by the same operator who makes the finenessdetermination.NOTE 6A little stopcock grease should be applied to the standardtaper connection. The efficiency of the connection can be determined byattaching the cell to the manometer, stoppering it, partially evacuating theo
47、ne arm of the manometer, then closing the valve. Any continuous drop inpressure indicates a leak in the system.NOTE 7The sample may be refluffed and reused for preparation of thetest bed, provided that it is kept dry and all tests are made within4hofthe opening of the sample.4.7 RecalibrationThe app
48、aratus shall be recalibrated(Note 8):4.7.1 At periodic intervals, the duration of which shall notexceed 212 years, to correct for possible wear on the plunger orpermeability cell, or upon receipt of evidence that the test is notproviding data in accordance with the precision and biasstatement in Sec
49、tion 8.4.7.2 If any loss in the manometer fluid occurs, recalibratestarting with 4.5,or4.7.3 If a change is made in the type or quality of the filterpaper used for the tests.NOTE 8It is suggested that a secondary sample be prepared and usedas a fineness standard for the check determinations of the instrumentbetween regular calibrations with the standard cement sample.5. Procedure5.1 Temperature of CementThe cement sample shall be atroom temperature when tested.5.2 Size of Test SampleThe weight of sample used for thetest shall be the same
