1、Designation: C 192/C 192M 07Standard Practice forMaking and Curing Concrete Test Specimens in theLaboratory1This standard is issued under the fixed designation C 192/C 192M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This practice covers procedures
3、for making and curingtest specimens of concrete in the laboratory under accuratecontrol of materials and test conditions using concrete that canbe consolidated by rodding or vibration as described herein.1.2 The values stated in either inch-pound units or SI unitsshall be regarded separately as stan
4、dard. The SI units areshown in brackets. The values stated in each system are notexact equivalents; therefore, each system shall be used inde-pendently of each other. Combining values from the twosystems may result in nonconformance.1.3 This standard does not purport to address all of thesafety conc
5、erns, 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. (WarningFreshhydraulic cementitious mixtures are caustic and may causechemical bu
6、rns to exposed skin and tissue upon prolongedexposure.2)2. Referenced Documents2.1 ASTM Standards:3C70 Test Method for Surface Moisture in Fine AggregateC 125 Terminology Relating to Concrete and ConcreteAggregatesC 127 Test Method for Density, Relative Density (SpecificGravity), and Absorption of C
7、oarse AggregateC 128 Test Method for Density, Relative Density (SpecificGravity), and Absorption of Fine AggregateC 138/C 138M Test Method for Density (Unit Weight),Yield, and Air Content (Gravimetric) of ConcreteC 143/C 143M Test Method for Slump of Hydraulic-Cement ConcreteC 172 Practice for Sampl
8、ing Freshly Mixed ConcreteC 173/C 173M Test Method for Air Content of FreshlyMixed Concrete by the Volumetric MethodC 231 Test Method for Air Content of Freshly MixedConcrete by the Pressure MethodC 330 Specification for Lightweight Aggregates for Struc-tural ConcreteC 403/C 403M Test Method for Tim
9、e of Setting of ConcreteMixtures by Penetration ResistanceC 470/C 470M Specification for Molds for Forming Con-crete Test Cylinders VerticallyC 494/C 494M Specification for Chemical Admixtures forConcreteC511 Specification for Mixing Rooms, Moist Cabinets,Moist Rooms, and Water Storage Tanks Used in
10、 theTesting of Hydraulic Cements and ConcretesC 566 Test Method for Total Evaporable Moisture Contentof Aggregate by DryingC 617 Practice for Capping Cylindrical Concrete Speci-mensC 1064/C 1064M Test Method for Temperature of FreshlyMixed Hydraulic-Cement ConcreteC 1077 Practice for Laboratories Te
11、sting Concrete and Con-crete Aggregates for Use in Construction and Criteria forLaboratory Evaluation2.2 American Concrete Institute Publications:4211.3 Practice for Selecting Proportions for No-Slump Con-crete309 Guide for Concrete Consolidation3. Significance and Use3.1 This practice provides stan
12、dardized requirements forpreparation of materials, mixing concrete, and making andcuring concrete test specimens under laboratory conditions.3.2 If specimen preparation is controlled as stipulatedherein, the specimens may be used to develop information forthe following purposes:1This practice is und
13、er the jurisdiction of ASTM Committee C09 on Concreteand ConcreteAggregates and is the direct responsibility of Subcommittee C09.61 onTesting for Strength.Current edition approved Aug. 1, 2007. Published September 2007. Originallyapproved in 1944. Last previous edition approved in 2006 as C 192/C 19
14、2M 06.2See section 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, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、refer to the standards Document Summary page onthe ASTM website.4Available from American Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333-9094, http:/www.aci-int.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Dri
16、ve, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.1 Mixture proportioning for project concrete,3.2.2 Evaluation of different mixtures and materials,3.2.3 Correlation with nondestructive tests, and3.2.4 Providing specimens for research purposes.NOTE 1The concrete test results for c
17、oncrete specimens made andcured using this practice are widely used. They may be the basis foracceptance testing for project concrete, research evaluations, and otherstudies. Careful and knowledgeable handling of materials, mixing con-crete, molding test specimens, and curing test specimens is neces
18、sary.Many laboratories performing this important work are independentlyinspected or accredited. Practice C 1077 identifies and defines duties,responsibilities, including minimum responsibilities of the laboratorypersonnel and minimum technical requirements for laboratory equipmentused. Many laborato
19、ries ensure qualified technicians by participating innational certification programs such as the American Concrete InstituteLaboratory Technician Program or an equivalent program.4. Apparatus4.1 Molds, GeneralMolds for specimens or fasteningsthereto in contact with the concrete shall be made of stee
20、l, castiron, or other nonabsorbent material, nonreactive with concretecontaining portland or other hydraulic cements. Molds shallconform to the dimensions and tolerances specified in themethod for which the specimens are required. Molds shall holdtheir dimensions and shape under all conditions of us
21、e.Watertightness of molds during use shall be judged by theirability to hold water poured into them. Test procedures forwatertightness are given in the section on Test Methods forElongation, Absorption, and Watertightness of SpecificationC 470/C 470M. A suitable sealant, such as heavy grease,modelin
22、g clay, or microcrystalline wax, shall be used wherenecessary to prevent leakage through the joints. Positive meansshall be provided to hold base plates firmly to the molds.Reusable molds shall be lightly coated with mineral oil or asuitable nonreactive release material before use.4.2 Cylinder Molds
23、:4.2.1 Molds for Casting Specimens Vertically shall conformto the requirements of 4.1 and Specification C 470/C 470M.4.2.2 Horizontal Molds for Creep Test Cylinders shallconform to the requirements of 4.1 and to the requirements forsymmetry and dimensional tolerance in the section on GeneralRequirem
24、ents except for verticality requirements of Specifica-tion C 470/C 470M. The use of horizontal molds is intendedonly for creep specimens that contain axially embedded straingages. Molds for creep cylinders to be filled while supported ina horizontal position shall have a filling slot parallel to the
25、 axisof the mold which extends the full length to receive theconcrete. The width of the slot shall be one half the diameter ofthe specimen. If necessary the edges of the slot shall bereinforced to maintain dimensional stability. Unless specimensare to be capped or ground to produce plane ends, the m
26、oldsshall be provided with two machined metal end plates at least1 in. 25 mm thick and the working surfaces shall comply withthe requirements for planeness and surface roughness given inthe section on Capping Plates of Practice C 617. Provisionshall be made for fixing both end plates firmly to the m
27、old. Theinside surface of each end plate shall be provided with at leastthree lugs or studs approximately 1 in. 25 mm long, firmlyfastened to the plate for embedment in the concrete. One baseplate shall be drilled from the inside at an angle to permit thelead wire from the strain gage to exit the sp
28、ecimen through theedge of the plate. Provision shall be made for accuratelypositioning the strain gage. All necessary holes shall be assmall as possible to minimize disturbance to subsequent strainmeasurements and shall be sealed to prevent leakage.4.3 Beam and Prism Molds shall be rectangular in sh
29、ape(unless otherwise specified) and of the dimensions required toproduce the desired specimen size. The inside surfaces of themolds shall be smooth and free from indentations. The sides,bottom, and ends shall be at right angles to each other and shallbe straight and true and free of warpage. Maximum
30、 variationfrom the nominal cross section shall not exceed18 in. 3 mmfor molds with depth or breadth of 6 in. 150 mm or more, or116 in. 2 mm for molds of smaller depth or breadth. Exceptfor flexure specimens, molds shall not vary from the nominallength by more than116 in. 2 mm. Flexure molds shall no
31、t beshorter than116 in. 2 mm of the required length, but mayexceed it by more than that amount.4.4 Tamping RodsTwo sizes are specified in ASTM meth-ods. Each shall be a round, straight steel rod with at least thetamping end rounded to a hemispherical tip of the samediameter as the rod. Both ends may
32、 be rounded, if preferred.4.4.1 Larger Rod,58 in. 16 mm in diameter and approxi-mately 24 in. 600 mm long.4.4.2 Smaller Rod,38 in. 10 mm in diameter and approxi-mately 12 in. 300 mm long.4.5 MalletsA mallet with a rubber or rawhide headweighing 1.25 6 0.50 lb 0.6 6 0.20 kg shall be used.4.6 Vibrator
33、s:4.6.1 Internal VibratorsThe vibrator frequency shall be atleast 7000 vibrations per minute 115 Hz while the vibrator isoperating in the concrete. The diameter of a round vibratorshall be no more than one fourth the diameter of the cylindermold or one fourth the width of the beam or prism mold. Oth
34、ershaped vibrators shall have a perimeter equivalent to thecircumference of an appropriate round vibrator. The combinedlength of the vibrator shaft and vibrating element shall exceedthe depth of the section being vibrated by at least 3 in. 75mm.NOTE 2For information on size and frequency of various
35、vibratorsand method to periodically check vibrator frequency, see ACI 309.4.6.2 External VibratorsThe two types of external vibra-tors permitted are either table or plank. The external vibratorfrequency shall be 3600 vibrations per minute 60 Hz orhigher.4.6.3 Provisions shall be made for clamping th
36、e moldsecurely to the apparatus for both types of vibrators.NOTE 3Vibratory impulses are frequently imparted to a table or plankvibrator through electromagnetic means, or by use of an eccentric weighton the shaft of an electric motor or on a separate shaft driven by a motor.4.7 Small ToolsTools and
37、items such as shovels, pails,trowels, wood float, blunted trowels, straightedge, feeler gage,scoops, rulers, rubber gloves, and metal mixing bowls shall beprovided.4.8 Slump ApparatusThe apparatus for measurement ofslump shall conform to the requirements of Test MethodC 143/C 143M.C 192/C 192M 0724.
38、9 Sampling and Mixing PanThe pan shall be flat-bottom and of heavy-gage metal, watertight, of convenientdepth, and of sufficient capacity to allow easy mixing by shovelor trowel of the entire batch; or, if mixing is by machine, toreceive the entire batch on discharge of the mixer and allowremixing i
39、n the pan by trowel or shovel.4.10 Wet-Sieving EquipmentIf wet-sieving is required, theequipment shall conform to the requirements of Practice C 172.4.11 Air Content ApparatusThe apparatus for measuringair content shall conform to the requirements of either TestMethods C 231 or C 173.4.12 ScalesScal
40、es for determining the mass of batches ofmaterials and concrete shall be accurate within 0.3 % of the testload at any point within the range of use.NOTE 4In general the mass of small quantities should not bedetermined on large capacity scales. In many applications the smallestmass determined on a sc
41、ale should be greater than about 10 % of themaximum capacity of the scale; however, this will vary with theperformance characteristics of the scale and the required accuracy of thedetermination. Acceptable scales used for determining the mass forconcrete materials preferably should determine mass ac
42、curately to about0.1 % of total capacity and the foregoing precaution is applicable.However, certain analytical and precision balances are exceptions to thisrule and should weigh accurately to 0.001 %. Particular care must beexercised in measuring small quantities of material by determining thediffe
43、rence between two much larger masses.4.13 Temperature Measuring DeviceThe temperaturemeasuring device shall conform to the requirements of TestMethod C 1064.4.14 Concrete MixerA power-driven concrete mixer shallbe a revolving drum, tilting mixer, or suitable revolving pan orrevolving-paddle mixer ca
44、pable of thoroughly mixing batchesof the prescribed sizes at the required slump.NOTE 5Apan mixer is usually more suitable for mixing concrete withless than 1-in. 25 mm slump than a revolving drum mixer. The rate ofrotation, degree of tilt, and rated capacity of tilting mixers are not alwayssuitable
45、for laboratory mixed concrete. It may be found desirable to reducethe rate of rotation, decrease the angle of tilt from the horizontal, and usethe mixer at somewhat less than the manufacturers rated capacity.5. Specimens5.1 Cylindrical SpecimensCylinder dimensions shall beas stipulated in the specif
46、ication, test method or practice for thelaboratory studies being performed and shall meet the require-ments of 5.4. If dimensions are not stipulated in a specification,test method, or practice, the specimen selected shall have alength that is twice the diameter and meet the requirements of5.4.NOTE 6
47、The same cylinder size should be used for the reference(control) concrete mixture and test concrete mixtures when conductingcomparative studies such as those required in Specification C 494/C 494M. For mixture proportioning of project concrete, it is preferable forthe cylinder size in the laboratory
48、 to be the same as that specified foracceptance testing.NOTE 7When molds in SI units are required and not available,equivalent inch-pound unit size mold should be permitted.5.1.1 Cylindrical specimens for tests other than creep shallbe molded and allowed to harden with the axis of the cylindervertic
49、al.5.1.2 Cylindrical creep specimens may be cast with thecylindrical axis either vertical or horizontal and allowed toharden in the position in which cast.5.2 Prismatic SpecimensBeams for flexural strength,prisms for freezing and thawing, bond, length change, volumechange, etc., shall be formed with their long axes horizontal,unless otherwise required by the method of test in question,and shall conform in dimension to the requirements of thespecific test method.5.3 Other SpecimensOther shapes and sizes of specimensfor pa
