1、Designation: C39/C39M 16bC39/C39M 17Standard 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 ye
2、ar 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 d
3、etermination 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 in
4、ch-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 dur
6、ing 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 expla
7、natory material. These notes shall not be considered asrequirements of the standard.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 of ConcreteC125 Term
8、inology 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 Construction MaterialsC8
9、73/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-Compacted Concrete in Cylin
10、der 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 Test Method for Obtaini
11、ng 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 MachinesManual of Aggregate and Concret
12、e Testing1 This test 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 Aug. 1, 2016Feb. 1, 2017. Published August 2016March 2017. Originally approved in 19
13、21. Last previous edition approved in 2016 asC39/C39M 16a.16b. DOI: 10.1520/C0039_C0039M-16B.10.1520/C0039_C0039M-17.2 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
14、the standards 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
15、accurately, 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 Ha
16、rbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. 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 distribute the load from the testing
17、 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 bearing surface. The lower bearingbl
18、ock 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 referred to as the testing machin
19、e 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 retainersof unbonded caps.3.2.5 upp
20、er 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 Method4.1 This test method co
21、nsists 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 area of the specimen.5. Signif
22、icance 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 onthe size and shape of the specim
23、en, 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 withPractices C31/C31M, C192/C192
24、M, C617/C617M, C1176/C1176M, C1231/C1231M, and C1435/C1435M, and Test MethodsC42/C42M, C873/C873Mand , and C873/C873MC1604/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 compliance with spe
25、cifications; 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 demonstration that is e
26、valuated 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 having sufficient
27、 capacity and capable of providing the rates ofloading prescribed in 7.58.5.C39/C39M 1726.1.1 Verify the accuracy of the testing machine in accordance with Practices E4, except that the verified loading range shallbe as required in 5.36.4. Verification is required:6.1.1.1 Within 13 months of the las
28、t 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 for the mass
29、 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 intermittent
30、ly, and without shock.If it has only one loading rate (meeting the requirements of 7.58.5), it must be provided with a supplemental means for loadingat a rate suitable for verification. This supplemental means of loading may be power or hand operated.6.1.2.2 The space provided for test specimens sha
31、ll 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 generally av
32、ailable 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 machine shall
33、 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 between themax
34、imum 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 follows:E 5A
35、 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.NOTE 1Provision shall be made for holding the ball in the socket and for holding the entire unit in the testing machine.T R rr = radius of spherica
36、l portion of upper bearing blockR = nominal radius of specimenT = thickness of upper bearing block extending beyond the sphereFIG. 1 Schematic Sketch of a Typical SphericalUpper Bearing BlockC39/C39M 1736.1.3.4 The report on the verification of a testing machine shall state within what loading range
37、 it was found to conform tospecification requirements rather than reporting a blanket acceptance or rejection. In no case 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 machin
38、e or loads within that portion of the range below 10 % of the maximum range capacity.6.1.3.5 In no case shall the loading 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
39、 calculation or by the use of a calibration diagramto obtain values within the required permissible variation.6.2 Bearing BlocksThe testing machine shall be equipped with two steel bearing blocks with hardened faces (Note 3), oneof which is a spherically seated block that will bear on the upper surf
40、ace of the specimen, and the other a solid block on whichthe specimen shall rest. Bearing faces of the blocks shall have a minimum dimension at least 3 % greater than the diameter of thespecimen to be tested. Except for the concentric circles described below, the bearing faces shall not depart from
41、a plane by morethan 0.02 mm 0.001 in. in any 150 mm 6 in. of blocks 150 mm 6 in. in diameter or larger, or by more than 0.02 mm 0.001in. in the diameter of any smaller block; and new blocks shall be manufactured within one half of this tolerance. When thediameter of the bearing face of the spherical
42、ly seated block exceeds the diameter of the specimen by more than 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 be inscribed to facilitateproper centering.upper and lower bearing blocks shall conform to the following requirements:NOTE
43、3It is desirable that the bearing faces of blocks used for compression testing of concrete have a Rockwell hardness of not less than 55 HRC.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 diamete
44、r of the specimen.6.2.3 Bottom Except for the inscribed concentric circles described in 6.2.4.7bearing blocks shall conform to the followingrequirements:, the bearing faces shall not depart from a plane by more than 0.02 mm 0.001 in. along any 150 mm 6 in. lengthfor bearing blocks with a diameter of
45、 150 mm 6 in. or larger, or by more than 0.02 mm 0.001 in. in any direction of smallerbearing blocks. New bearing blocks shall be manufactured within one half of this tolerance.5.2.1.1 The bottom bearing block is specified for the purpose of providing a readily machinable surface for maintenance of
46、thespecified surface conditions (Note 4). The top and bottom surfaces shall be parallel to each other. If the testing machine is sodesigned that the platen itself is readily maintained in the specified surface condition, a bottom block is not required. Its leasthorizontal dimension shall be at least
47、 3 % greater than the diameter of the specimen to be tested. Concentric circles as describedin 5.2 are optional on the bottom block.NOTE 4The block may be fastened to the platen of the testing machine.NOTE 3It is desirable that the bearing faces of bearing blocks have a Rockwell hardness at least 55
48、 HRC as determined by Test Methods E18.5.2.1.2 Final centering must be made with reference to the upper spherical block. When the lower bearing block is used to assistin centering the specimen, the center of the concentric rings, when provided, or the center of the block itself must be directly belo
49、wthe center of the spherical head. Provision shall be made on the platen of the machine to assure such a position.NOTE 4Square bearing faces are permissible for the bearing blocks.5.2.1.3 The bottom bearing block shall be at least 25 mm 1 in. thick when new, and at least 22.5 mm 0.9 in. thick after anyresurfacing operations.6.2.4 Upper Bearing BlockThe spherically seated upper bearing block shall conform to the following requirements:5.2.2.1 The maximum diameter of the bearing face of the suspended spherically seated bl
copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1