1、Designation: C39/C39M 17aC39/C39M 17bStandard Test Method forCompressive Strength of Cylindrical Concrete Specimens1This standard is issued under the fixed designation C39/C39M; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the y
2、ear 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. Department of Defense.1. Scope*1.1 This test method covers
3、determination of compressive strength of cylindrical concrete specimens such as molded cylindersand drilled cores. It is limited to concrete having a density in excess of 800 kg/m3 50 lb/ft3.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The i
4、nch-pound units areshown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be usedindependently of the other. Combining values from the two systems may result in non-conformance with the standard.1.3 This standard does not purport to address all
5、 of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. (WarningMeans should be provided to contain concrete fragments du
6、ring sudden rupture of specimens.Tendency for sudden rupture increases with increasing concrete strength and it is more likely when the testing machine is relativelyflexible. The safety precautions given in the Manual are recommended.)1.4 The text of this standard references notes which provide expl
7、anatory material. These notes shall not be considered asrequirements of the standard.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guid
8、es and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C31/C31M Practice for Making and Curing Concrete Test Specimens in the FieldC42/C42M Test Method for Obtaining and Testing Drilled Cores and Sawed Beams
9、 of ConcreteC125 Terminology Relating to Concrete and Concrete AggregatesC192/C192M Practice for Making and Curing Concrete Test Specimens in the LaboratoryC617/C617M Practice for Capping Cylindrical Concrete SpecimensC670 Practice for Preparing Precision and Bias Statements for Test Methods for Con
10、struction MaterialsC873/C873M Test Method for Compressive Strength of Concrete Cylinders Cast in Place in Cylindrical MoldsC1077 Practice forAgencies Testing Concrete and ConcreteAggregates for Use in Construction and Criteria for TestingAgencyEvaluationC1176/C1176M Practice for Making Roller-Compac
11、ted Concrete in Cylinder Molds Using a Vibrating TableC1231/C1231M Practice for Use of Unbonded Caps in Determination of Compressive Strength of Hardened CylindricalConcrete SpecimensC1435/C1435M Practice for Molding Roller-Compacted Concrete in Cylinder Molds Using a Vibrating HammerC1604/C1604M Te
12、st Method for Obtaining and Testing Drilled Cores of ShotcreteE4 Practices for Force Verification of Testing MachinesE18 Test Methods for Rockwell Hardness of Metallic MaterialsE74 Practice of Calibration of Force-Measuring Instruments for Verifying the Force Indication of Testing Machines1 This tes
13、t method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.61 onTesting for Strength.Current edition approved March 15, 2017Aug. 1, 2017. Published May 2017August 2017. Originally approved in 1921. Last previous e
14、dition approved in 2017 asC39/C39MC39/C39M 17a. 17. DOI: 10.1520/C0039_C0039M-17A.10.1520/C0039_C0039M-17B.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standa
15、rds Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of 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
16、, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive
17、, PO Box C700, West Conshohocken, PA 19428-2959. United States1Manual of Aggregate and Concrete Testing3. Terminology3.1 DefinitionsFor definitions of terms used in this practice, refer to Terminology C125.3.2 Definitions of Terms Specific to This Standard:3.2.1 bearing block, nsteel piece to distri
18、bute the load from the testing machine to the specimen.3.2.2 lower bearing block, nsteel piece placed under the specimen to distribute the load from the testing machine to thespecimen.3.2.2.1 DiscussionThe lower bearing block provides a readily machinable surface for maintaining the specified bearin
19、g surface. The lower bearingblock may also be used to adapt the testing machine to various specimen heights. The lower bearing block is also referred to asbottom block,plain block, and false platen.3.2.3 platen, nprimary bearing surface of the testing machine.3.2.3.1 DiscussionThe platen is also ref
20、erred to as the testing machine table.3.2.4 spacer, nsteel piece used to elevate the lower bearing block to accommodate test specimens of various heights.3.2.4.1 DiscussionSpacers are not required to have hardened bearing faces because spacers are not in direct contact with the specimen or the retai
21、nersof unbonded caps.3.2.5 upper bearing block, nsteel assembly suspended above the specimen that is capable of tilting to bear uniformly on thetop of the specimen.3.2.5.1 DiscussionThe upper bearing block is also referred to as the spherically seated block and the suspended block.4. Summary of Test
22、 Method4.1 This test method consists of applying a compressive axial load to molded cylinders or cores at a rate which is within aprescribed range until failure occurs. The compressive strength of the specimen is calculated by dividing the maximum loadattained during the test by the cross-sectional
23、area of the specimen.5. Significance and Use5.1 Care must be exercised in the interpretation of the significance of compressive strength determinations by this test methodsince strength is not a fundamental or intrinsic property of concrete made from given materials. Values obtained will depend onth
24、e size and shape of the specimen, batching, mixing procedures, the methods of sampling, molding, and fabrication and the age,temperature, and moisture conditions during curing.5.2 This test method is used to determine compressive strength of cylindrical specimens prepared and cured in accordance wit
25、hPractices C31/C31M, C192/C192M, C617/C617M, C1176/C1176M, C1231/C1231M, and C1435/C1435M, and Test MethodsC42/C42M, C873/C873M, and C1604/C1604M.5.3 The results of this test method are used as a basis for quality control of concrete proportioning, mixing, and placingoperations; determination of com
26、pliance with specifications; control for evaluating effectiveness of admixtures; and similar uses.5.4 The individual who tests concrete cylinders for acceptance testing shall meet the concrete laboratory technicianrequirements of Practice C1077, including an examination requiring performance demonst
27、ration that is evaluated by anindependent examiner.NOTE 1Certification equivalent to the minimum guidelines for ACI Concrete Laboratory Technician, Level I or ACI Concrete Strength TestingTechnician will satisfy this requirement.6. Apparatus6.1 Testing MachineThe testing machine shall be of a type h
28、aving sufficient capacity and capable of providing the rates ofloading prescribed in 8.5.C39/C39M 17b26.1.1 Verify the accuracy of the testing machine in accordance with Practices E4, except that the verified loading range shallbe as required in 6.4. Verification is required:6.1.1.1 Within 13 months
29、 of the last calibration,6.1.1.2 On original installation or immediately after relocation,6.1.1.3 Immediately after making repairs or adjustments that affect the operation of the force applying system or the valuesdisplayed on the load indicating system, except for zero adjustments that compensate f
30、or the mass of bearing blocks or specimen,or both, or6.1.1.4 Whenever there is reason to suspect the accuracy of the indicated loads.6.1.2 DesignThe design of the machine must include the following features:6.1.2.1 The machine must be power operated and must apply the load continuously rather than i
31、ntermittently, and without shock.If it has only one loading rate (meeting the requirements of 8.5), it must be provided with a supplemental means for loading ata rate suitable for verification. This supplemental means of loading may be power or hand operated.6.1.2.2 The space provided for test speci
32、mens shall be large enough to accommodate, in a readable position, an elasticcalibration device which is of sufficient capacity to cover the potential loading range of the testing machine and which complieswith the requirements of Practice E74.NOTE 2The types of elastic calibration devices most gene
33、rally available and most commonly used for this purpose are the circular proving ring orload cell.6.1.3 AccuracyThe accuracy of the testing machine shall be in accordance with the following provisions:6.1.3.1 The percentage of error for the loads within the proposed range of use of the testing machi
34、ne shall not exceed 61.0 %of the indicated load.6.1.3.2 The accuracy of the testing machine shall be verified by applying five test loads in four approximately equal incrementsin ascending order. The difference between any two successive test loads shall not exceed one third of the difference betwee
35、n themaximum and minimum test loads.6.1.3.3 The test load as indicated by the testing machine and the applied load computed from the readings of the verificationdevice shall be recorded at each test point. Calculate the error, E, and the percentage of error, Ep, for each point from these dataas foll
36、ows:E 5A 2B (1)Ep 5100A 2B!/Bwhere:A = load, kN lbf indicated by the machine being verified, andB = applied load, kN lbf as determined by the calibrating device.6.1.3.4 The report on the verification of a testing machine shall state within what loading range it was found to conform toT R rr = radius
37、 of spherical portion of upper bearing blockR = nominal radius of specimenT = thickness of upper bearing block extending beyond the sphereFIG. 1 Schematic Sketch of a Typical Upper Bearing BlockC39/C39M 17b3specification requirements rather than reporting a blanket acceptance or rejection. In no cas
38、e shall the loading range be stated asincluding loads below the value which is 100 times the smallest change of load estimable on the load-indicating mechanism ofthe testing machine or loads within that portion of the range below 10 % of the maximum range capacity.6.1.3.5 In no case shall the loadin
39、g range be stated as including loads outside the range of loads applied during the verificationtest.6.1.3.6 The indicated load of a testing machine shall not be corrected either by calculation or by the use of a calibration diagramto obtain values within the required permissible variation.6.2 Bearin
40、g BlocksThe upper and lower bearing blocks shall conform to the following requirements:6.2.1 Bearing blocks shall be steel with hardened bearing faces (Note 3).6.2.2 Bearing faces shall have dimensions at least 3 % greater than the nominal diameter of the specimen.6.2.3 Except for the inscribed conc
41、entric circles described in 6.2.4.7, the bearing faces shall not depart from a plane by morethan 0.02 mm 0.001 in. along any 150 mm 6 in. length for bearing blocks with a diameter of 150 mm 6 in. or larger, or bymore than 0.02 mm 0.001 in. in any direction of smaller bearing blocks. New bearing bloc
42、ks shall be manufactured within onehalf of this tolerance.NOTE 3It is desirable that the bearing faces of bearing blocks have a Rockwell hardness at least 55 HRC as determined by Test Methods E18.NOTE 4Square bearing faces are permissible for the bearing blocks.6.2.4 Upper Bearing BlockThe upper bea
43、ring block shall conform to the following requirements:6.2.4.1 The upper bearing block shall be spherically seated and the center of the sphere shall coincide with the center of thebearing face within 65 % of the radius of the sphere.6.2.4.2 The ball and the socket shall be designed so that the stee
44、l in the contact area does not permanently deform when loadedto the capacity of the testing machine.NOTE 5The preferred contact area is in the form of a ring (described as preferred bearing area) as shown in Fig. 1.6.2.4.3 Provision shall be made for holding the upper bearing block in the socket. Th
45、e design shall be such that the bearing facecan be rotated and tilted at least 4 in any direction.6.2.4.4 If the upper bearing block is a two-piece design composed of a spherical portion and a bearing plate, a mechanical meansshall be provided to ensure that the spherical portion is fixed and center
46、ed on the bearing plate.6.2.4.5 The diameter of the sphere shall be at least 75 % of the nominal diameter of the specimen. If the diameter of the sphereis smaller than the diameter of the specimen, the portion of the bearing face extending beyond the sphere shall have a thicknessnot less than the di
47、fference between the radius of the sphere and radius of the specimen (see Fig. 1). The least dimension of thebearing face shall be at least as great as the diameter of the sphere.6.2.4.6 The dimensions of the bearing face of the upper bearing block shall not exceed the following values:Nominal Diame
48、terof Specimen,mm in.Maximum Diameterof Round BearingFace, mm in.Maximum Dimensionsof Square BearingFace, mm in.50 2 105 4 105 by 105 4 by 475 3 130 5 130 by 130 5 by 5100 4 165 6.5 165 by 165 6.5 by 6.5150 6 255 10 255 by 255 10 by 10200 8 280 11 280 by 280 11 by 116.2.4.7 If the diameter of the be
49、aring face of the upper bearing block exceeds the nominal diameter of the specimen by morethan 13 mm 0.5 in., concentric circles not more than 0.8 mm 0.03 in. deep and not more than 1 mm 0.04 in. wide shall beinscribed on the face of upper bearing block to facilitate proper centering.6.2.4.8 At least every six months, or as specified by the manufacturer of the testing machine, clean and lubricate the curvedsurfaces of the socket and of the spherical portion of the upper bearing block. The lubric
