1、Designation: C170/C170M 14aC170/C170M 15Standard 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 las
2、t 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 samplin
3、g, 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 inde
4、pendently 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.2. Referenced Documents2.1 ASTM Standards:2C39 Test Method for Compressive Strength of Cylindrical Concrete SpecimensC119 Terminology Relating to Dimension StoneC1799 Guide to Dimension Stone Test Specimen Sa
6、mpling 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 TemperaturesE4 Practi
7、ces 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. Thistest method also pr
8、ovides 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 required load at a uni
9、form rate as prescribed in Section 9 andapplying load in a steady manner as to avoid sudden or rapid load changes.5.3 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)
10、when not loaded. The spherical surfaces shall be well lubricated, and thecenter of curvature shall be aligned within the surface of contact with the specimen.1 This test method is under the jurisdiction of ASTM Committee C18 on Dimension Stone and is the direct responsibility of Subcommittee C18.01
11、on Test Methods.Current edition approved Oct. 15, 2014May 1, 2015. Published November 2014July 2015. Originally approved in 1941. Last previous edition approved in 2014 asC170/C170M14.14a. DOI: 10.1520/C0170_C0170M-14A.10.1520/C0170_C0170M-15.2 For referencedASTM standards, visit theASTM website, ww
12、w.astm.org, or contactASTM 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 wh
13、at changes have been 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 th
14、e official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.4 Fig. 1 illustrates the correct alignment of a specimen and the typical components of a testing machine conforming to theserequirements.6. Sampling6.1 The sample s
15、hall 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 sample may be selected by thepurchaser or his authorized representative from quarried stone o
16、r 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 for determining the variation in compressive strength.NOTE 1Refer to Guide C1799
17、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 diameteror lateral dimension (distance between opposite vertical surfaces) shall
18、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 apparatus) to the diameter or lateraldimension shall be between 0.9:1.0 and 1.1
19、: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 surfaces in contact with the testing apparatus shall have a fine abrasive finish, and the other surfaces shall have afine sawn finish (Expla
20、natory Note 5). The surfaces in contact with the testing apparatus shall be ground or lapped to a flatnesstolerance of plus or minus 0.005 in. 0.1 mm, and shall not depart from perpendicular to the longitudinal axis of the specimenby more than 0.25 deg.7.5 At least five specimens shall be prepared f
21、or each test condition. Final test conditions are determined by the projectconditions and specified with 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 o
22、rientation), requiring a minimum of 20specimens. Fig. 2a and Fig. 2b illustrate the proper placement of test specimens within a testing apparatus for the two mostcommon rift orientations. The load-bearing surfaces shall be finished by grinding to as nearly true and parallel planes (ExplanatoryNote 5
23、) as practicable.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.8. Conditioning8.1 Before testing the specimens in a dry condition, dry them for 48 h at 140 6
24、 4F 60 6 2C. At the 46th, 47th, and 48thh, weigh the specimens to ensure that the weight is the same. If the weight continues to drop, continue to dry the specimens untilthere are 3 successive hourly readings with the same weight. After removing the specimens from the oven, cool them to roomtemperat
25、ure in a desiccator before testing them.8.2 Before testing the specimens in a wet condition, immerse them in water for 48 h at 72 6 4F 22 6 2C. Test themimmediately upon removal from the bath, wiping the specimens free of surface water.FIG. 1 Diagram of a Specimen Properly Aligned within a Testing A
26、pparatus Suitable for Compressive Strength TestingC170/C170M 1529. Procedure9.1 The load-bearing area of each specimen shall be calculated from measurements taken midway between the surfaces incontact with the testing apparatus and calculated to the nearest 0.1 in.260 mm2. An alternate approach for
27、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 initial seating load that will hold the specimen in place but stillpermit hand adjustme
28、nt 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.9.3 Apply load at a uniform rate not exceeding 100 psi/s 0.5 MPa/s.9.4 Apply the lo
29、ad 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 compressive strength of each specimen as follows:C 5W/A (1)where:C = compressive streng
30、th 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.Round each individual result to the nearest 100 psi 1 MPa.11. Report11.1 The report shall include the following:11.1.1 Date,11.1.2 Testing agency,11.1.3 Personnel r
31、esponsible 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 when samplewas taken and trade name or grade of stone,11.1.6 Stone type,11.1.7 Specimen d
32、imensions,11.1.8 Stone specimen orientations tested,11.1.9 Conditioning procedures used,11.1.10 Individual test results for each specimen,11.1.11 Average value of the test results for each test condition (wet, dry, perpendicular to rift, parallel to rift, etc.) using thefollowing equation:Cav 5 sum
33、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:(a) Loading Perpendicular to Bedding Plane or Rift (b) Loading Parallel to Bedding Plane or RiftFIG. 2
34、 Orientation of Specimen in a Testing Apparatus with Respect to Bedding Plane or RiftC170/C170M 153S 5sum of test 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 an
35、d preparatory requirements.12. Precision and Bias12.1 Individual variations in a natural product may result in deviation from accepted values. A precision section will be addedwhen sufficient data are available to indicate acceptable tolerances in repeatability and reproducibility.13. Keywords13.1 c
36、ompressive strength; dimension stone; stone; testEXPLANATORY NOTESNOTE 1For very coarse-grain materials like some 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 w
37、ith a height to lateral dimension proportion1:1. This specimen shape differs from the standard shape specimens for determination of compressive strength of rock specimens required by Test MethodD7012. Variation from the required cube specimen, dimensions, and height ot lateral dimension proportions
38、of 1:1 has been found to result in significantvariations in compressive strength values. Comparison with compressive 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
39、and industry practices, this standard doesnot allow for deviation from the required specimen shape and dimensions.NOTE 3In some materials, such as granite, three directions with respect to fissility are recognized, as follows: “rift” (the plane of easiest splitting),“grain” (the plane of next easies
40、t splitting), and “head-grain” (the plane of hardest splitting). Occasionally, tests are required for determining the strengthperpendicular to each of these directions. In such cases, the sample shall be marked at the quarry to show which faces are grain, rift, and head-grain, andthe required number
41、 of specimens shall be prepared with load-bearing faces parallel to each of these planes and properly labeled for the various tests.NOTE 4Prepared specimens must meet the required tolerances for testing. Deviation from these tolerances can have a measurable impact on the testresults and produce valu
42、es that under or over-estimate the compressive strength of the stone. For procedures helpful in verifying tolerances are being met,refer to Practices D4543.NOTE 5Accuracy of test results depends largely on uniform distribution of the load over the bearing faces. In order to grind the surfaces to rea
43、sonablytrue planes, considerable care is necessary. the following procedure is suggested: Assuming that the specimen is a cube or cylinder and the load is 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 t
44、hese 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 No. 80emery and water. The specimen should be grasped as near the surface of the plate as possible to prevent rocking of the specimen.Asatisfacto
45、ry 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. 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 permi
46、t 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 notched metalbetween the specimen and one chuck point. This causes the specimen to be placed somewhat off-center but does not interfere with the sur
47、facing 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 this waycommonly give considerably higher test results than specimens prepared by hand.ASTM International takes no position respecting the validi
48、ty 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 subjec
49、t to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM C
