1、Designation: C170/C170M 16C170/C170M 17Standard Test Method forCompressive Strength of Dimension Stone1This standard is issued under the fixed designation C170/C170M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval.A superscript 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. Scope1.1 This test method covers the sampling
3、, preparation of specimens, and determination of the compressive strength ofdimension stone.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used indep
4、endently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety
5、and health practices and determine the applicability of regulatorylimitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards
6、, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C39 Test Method for Compressive Strength of Cylindrical Concrete SpecimensC119 Terminology Relating to Dimension StoneC1799 Guide to Dimension Sto
7、ne Test Specimen Sampling and PreparationD4543 Practices for Preparing Rock Core as Cylindrical Test Specimens and Verifying Conformance to Dimensional and ShapeTolerancesD7012 Test Methods for Compressive Strength and Elastic Moduli of Intact Rock Core Specimens under Varying States ofStress and Te
8、mperaturesE4 Practices for Force Verification of Testing Machines3. Terminology3.1 DefinitionsAll definitions are in accordance with Terminology C119.4. Significance and Use4.1 This test method is useful in indicating the differences in compressive strength between the various dimension stones. This
9、test method also provides one element in comparing stones of the same type.5. Apparatus5.1 The testing machine used shall conform to the requirements of Test Method C39, Section 5, including the calibrationrequirements of Practices E4.5.2 The testing machine used shall be capable of applying the req
10、uired load at a uniform rate as prescribed in Section 9 andapplying load in a steady manner as to avoid sudden or rapid load changes.1 This test method is under the jurisdiction of ASTM Committee C18 on Dimension Stone and is the direct responsibility of Subcommittee C18.01 on Test Methods.Current e
11、dition approved March 15, 2016April 1, 2017. Published March 2016April 2017. Originally approved in 1941. Last previous edition approved in 20152016 asC170/C170M15b.16. DOI: 10.1520/C0170_C0170M-16.10.1520/C0170_C0170M-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contac
12、tASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to 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
13、made to the previous version. Becauseit may not be technically possible to adequately depict all changes 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.C
14、opyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.3 The spherical bearing block of the testing machine shall be suspended from the upper head so that the contact plate remainsin a central position (spherical surfaces in full contact) w
15、hen not loaded. The spherical surfaces shall be well lubricated, and thecenter of curvature shall be aligned within the surface of contact with the specimen.5.4 Fig. 1 illustrates the correct alignment of a specimen and the typical components of a testing machine conforming to theserequirements.6. S
16、ampling6.1 The sample shall be selected to represent a true average of the type or grade of stone under consideration and shall be ofthe quality supplied to the market in finished form under the type designation to be tested. The samples may be selected by thepurchaser or his authorized representati
17、ve from quarried stone or taken from the natural ledge and shall be of adequate size topermit the preparation of the desired number of test specimens. When perceptible variations occur, the purchaser may select asmany samples as are necessary to determine the variation in compressive strength.6.2 Co
18、mpressive strength testing of specimens in more than two orientations with respect to splitting, including: rift (plane ofeasiest splitting), grain (plane of next easiest splitting), and head grain (plane of hardest splitting) can be desired for some stonetypes. Depending on the stone type and appli
19、cation, testing of additional orientations may be appropriate.An additional ten samplesare necessary for testing each additional orientation in both wet and dry conditions (five for wet and five for dry). The requirednumber of specimens shall be prepared with the load-bearing surface for each of the
20、se orientations properly labeled for testing.NOTE 1Refer to Guide C1799 for additional information on selecting, preparing, and conditioning test specimens.7. Test Specimens7.1 The test specimens may be cubes or right cylinders and shall be cut from the sample with saws or core drills. The diametero
21、r lateral dimension (distance between opposite vertical surfaces) shall be not less than 2 in. 50 mm dimensional to accommodatevariations in the grain size or composition of the sample (Explanatory Note 1).7.2 The ratio of height (the distance between the surfaces in contact with the testing apparat
22、us) to the diameter or lateraldimension shall be between 0.9:1.0 and 1.1:1.0 (Explanatory Note 2).7.3 The sides of the specimen shall be smooth and straight to within 0.02 in. 0.5 mm over the full height of the specimen.7.4 The two load bearing surfaces in contact with the testing apparatus shall ha
23、ve a fine abrasive finish, and the other surfacesshall have a fine sawn finish. They shall be finished by grinding to as nearly true and parallel planes as practicable (ExplanatoryNote 3). The surfaces in contact with the testing apparatus shall be ground or lapped to a flatness tolerance of plus or
24、 minus 0.005in. 0.1 mm, and shall not depart from perpendicular to the longitudinal axis of the specimen by more than 0.25 deg. (ExplanatoryNote 4).7.5 At least five specimens shall be prepared for each test condition. Final test conditions are determined by the projectconditions and specified with
25、the testing request. Typically, testing includes wet and dry conditions both perpendicular and parallelto the stone rift (plane of easiest splitting, typically consistent with the bedding plane orientation), requiring a minimum of 20specimens. Fig. 2a and Fig. 2b illustrate the proper placement of t
26、est specimens within a testing apparatus for the two mostcommon rift orientations.7.6 The load-bearing surfaces and the direction of rift shall be marked on each specimen.7.7 Use of capping materials or end surfacing treatments other than grinding shall not be permitted.FIG. 1 Diagram of a Specimen
27、Properly Aligned within a Testing Apparatus Suitable for Compressive Strength TestingC170/C170M 1728. Conditioning8.1 Before testing the specimens in a dry condition, dry them for at least 48 h at 140 6 4F 60 6 2C. At the 46th, 47th, and48th h, weigh the specimens to ensure that the weight is the sa
28、me. If the weight continues to drop, continue to dry the specimensuntil there are 3 successive hourly readings with the same weight.After removing the specimens from the oven, cool them to roomtemperature in a desiccator before testing them.8.2 Before testing the specimens in a wet condition, immers
29、e them in water for at least 48 h at 72 6 4F 22 6 2C. Test themimmediately upon removal from the bath, wiping the specimens free of surface water.9. Procedure9.1 The load-bearing area of each specimen shall be calculated from measurements taken midway between the surfaces incontact with the testing
30、apparatus and calculated to the nearest 0.1 in.260 mm2. An alternate approach for determining theload-bearing area is to calculate the areas of the top and bottom bearing surfaces to the nearest 0.1 in.260 mm2 and average thesevalues.9.2 Center the specimens in the testing machine and apply an initi
31、al seating load that will hold the specimen in place but stillpermit hand adjustment of the contact plate on the specimen. Rotate the contact plate back and forth through an angle ofapproximately 30 deg. to properly seat the spherical block, but do not move the specimen out of the central position.9
32、.3 Apply load at a uniform rate not exceeding 100 psi/s 0.5 MPa/s.9.4 Apply the load until specimen failure. Failure of the specimen is defined as the inability of the specimen to resist additionalload.9.5 Record the load at failure to the nearest 100 lb 500 N.10. Calculation10.1 Calculate the compr
33、essive strength of each specimen as follows:C 5W/A (1)where:C = compressive strength of the specimen, psi MPaW = total load, lbf N, on the specimen at failure, andA = calculated area of the bearing surface in in.2 mm2.10.2 Report each individual result to three significant digits.11. Report11.1 The
34、report shall include the following:11.1.1 Date,11.1.2 Testing agency,11.1.3 Personnel responsible for the test results,11.1.4 Description of the testing equipment or apparatus used,11.1.5 Identification of the samples, including name and location of the quarry, name or position of the ledge, date wh
35、en samplewas taken and trade name or grade of stone,11.1.6 Stone type,11.1.7 Specimen dimensions,11.1.8 Stone specimen orientations tested,(a) Loading Perpendicular to Bedding Plane or Rift (b) Loading Parallel to Bedding Plane or RiftFIG. 2 Orientation of Specimen in a Testing Apparatus with Respec
36、t to Bedding Plane or RiftC170/C170M 17311.1.9 Conditioning procedures used,11.1.9.1 Amount of time the specimens were dried,11.1.9.2 Amount of time the specimens were immersed,11.1.10 Individual test results for each specimen,11.1.11 Average value of the test results for each test condition (wet, d
37、ry, perpendicular to rift, parallel to rift, etc.) using thefollowing equation:Cav 5 sum of individual test results for each test condition! (2)number of tests for each test condition!11.1.12 Standard deviation(s) of the test results for each test condition using the following relation:S 5sum of tes
38、t result 2 Cav!2 (3)number of test 2 1!#1211.1.13 Statements describing deviations from the above-described testing procedures, as well as any variance from the testspecimen dimensional and preparatory requirements.12. Precision and Bias12.1 Individual variations in a natural product may result in d
39、eviation from accepted values. A precision section will be addedwhen sufficient data are available to indicate acceptable tolerances in repeatability and reproducibility.13. Keywords13.1 compressive strength; dimension stone; stone; testEXPLANATORY NOTESNOTE 1For very coarse-grain materials like som
40、e of the granites, the diameter of the specimen should not be less than 2.5 in. 65 mm.NOTE 2The compressive strength of dimension stone has historically been determined on cube specimens with a height to lateral dimension proportion1:1. This specimen shape differs from the standard shape specimens f
41、or determination of compressive strength of rock specimens required by Test MethodD7012. Variation from the required cube specimen, dimensions, and height of lateral dimension proportions of 1:1 has been found to result in significantvariations in compressive strength values. Comparison with compres
42、sive strength of rock specimens determined by Test Method D7012 requires the useof correction factors. For consistency with historical compressive strength values determined by C170/C170M and industry practices, this standard doesnot allow for deviation from the required specimen shape and dimension
43、s.NOTE 3Accuracy of test results depends largely on uniform distribution of the load over the bearing faces. In order to grind the surfaces to reasonablytrue planes, considerable care is necessary. the following procedure is suggested: Assuming that the specimen is a cube or cylinder and the load is
44、 to beapplied to the ends; mark two adjacent sides for reference, then grind the ends on a grinding wheel or lap until they are perpendicular to these referencesides as gaged by a machinist square. Complete the grinding by rubbing the ends on a smooth machine-planed surface of a cast iron plate with
45、 No. 80emery and water. The specimen should be grasped as near the surface of the plate as possible to prevent rocking of the specimen.Asatisfactory mechanicalmeans of finishing the bearing surfaces of the specimens is to place them in a chuck in a lathe and surface the ends with a tool post grinder
46、. This grinderconsists of a small motor and arbor carrying an abrasive wheel which turns at about 5000 r/min. A three-point chuck is used to permit the surfacing ofcylindrical, square prism, or cubical specimens. When the square-type specimen is used it will be necessary to place a small piece of no
47、tched metalbetween the specimen and one chuck point. This causes the specimen to be placed somewhat off-center but does not interfere with the surfacing process.The surface can be tested for flatness by holding a straightedge on the surface and viewing it before a strong light. Specimens finished in
48、 this waycommonly give considerably higher test results than specimens prepared by hand.NOTE 4Prepared specimens should meet the required tolerances for testing. Deviation from these tolerances can have a measurable impact on the testresults and produce values that under or over-estimate the compres
49、sive strength of the stone. For procedures helpful in verifying tolerances are being met,refer to Practices D4543.ASTM International takes no position respecting the validity of any patent rights 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 a
