1、Designation: C 170 06Standard Test Method forCompressive Strength of Dimension Stone1This standard is issued under the fixed designation C 170; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in
2、parentheses indicates the year of last reapproval. Asuperscript 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. Scope1.1 This test method covers the sampling, preparation ofspecimens,
3、and determination of the compressive strength ofdimension stone.1.2 This standard does not purport to address all of thesafety concerns, 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 appli
4、ca-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C119 Terminology Relating to Dimension StoneE4 Practices for Force Verification of Testing Machines3. Terminology3.1 DefinitionsAll definitions are in accordance with Ter-minology C119.4. Significance and Use
5、4.1 This test method is useful in indicating the differences incompressive strength between the various dimension stones.This test method also provides one element in comparingstones of the same type.5. Apparatus5.1 Any testing machine conforming to Practices E4and tothe speed of testing requirement
6、s prescribed in Section 9 of thistest method may be used.5.2 In vertical testing machines, the spherical bearing blockshall be suspended from the upper head of the machine in sucha manner that the contact plate remains in a central position(spherical surfaces in full contact) when not loaded. Thesph
7、erical surfaces shall be well lubricated, and the center ofcurvature shall lie in the surface of contact with the specimen.6. Sampling6.1 The sample shall be selected to represent a true averageof the type or grade of stone under consideration and shall beof the quality supplied to the market in fin
8、ished form under thetype designation to be tested. The sample may be selected bythe purchaser or his authorized representative from quarriedstone or taken from the natural ledge and shall be of adequatesize to permit the preparation of the desired number of testspecimens. When perceptible variations
9、 occur, the purchasermay select as many samples as are necessary for determiningthe variation in compressive strength.7. Test Specimens7.1 The test specimens may be cubes or cylinders and shallbe cut from the sample with saws or core drills. The diameteror lateral dimension (distance between opposit
10、e vertical faces)shall be not less than 2 in. (50.8 mm) (Explanatory Note 1), andthe ratio of height (Explanatory Note 2) to diameter or lateraldimension shall be 1:1. At least five specimens shall beprepared for each condition of the test; that is, when thecompressive strength is desired for the we
11、t and dry conditionsbut in only one direction, such as perpendicular to the bed (orrift) (see Fig. 1(a), ten specimens will be required. For wet anddry strength tests both perpendicular and parallel to the bed (orrift) (see Fig. 1(a) and (b), twenty specimens are required(Explanatory Note 3). The lo
12、ad-bearing faces shall be finishedby grinding to as nearly true and parallel planes (ExplanatoryNote 4) as practicable.7.2 The load-bearing surfaces and the direction of bedding(or rift) shall be marked on each specimen after finishing.7.3 The load-bearing areas of the specimen shall be calcu-lated
13、from measurements taken midway between the load-bearing surfaces. The dimensions of the specimens shall bemeasured to the nearest 0.02 in. (0.5 mm) and the load-bearingareas calculated to the nearest 0.04 in.2(0.26 cm2).1This test method is under the jurisdiction of ASTM Committee C18 onDimension St
14、one and is the direct responsibility of Subcommittee C18.01 on TestMethods.Current edition approved Oct. 15, 2006. Published November 2006. Originallyapproved in 1941. Last previous edition approved in 1999 as C 170 90(1999).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcon
15、tact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.8. Conditioning8.1 Be
16、fore testing the specimens in a dry condition, drythem for 48 h at 60 6 2C (140 6 4F). At the 46th, 47th, and48th h, weigh the specimens to ensure that the weight is thesame. If the weight continues to drop, continue to dry thespecimens until there are 3 successive hourly readings with thesame weigh
17、t. After removing the specimens from the oven,cool them to room temperature in a desiccator before testingthem.8.2 Before testing the specimens in a wet condition, im-merse them in water for 48 h at 22 6 2C (72 6 4F). Testthem immediately upon removal from the bath, wiping thespecimens free of surfa
18、ce water.9. Procedure9.1 Center the specimens in the testing machine and applythe initial load at a rate that will permit hand adjustment of thecontact plate on the specimen. Rotate the plate back and forththrough an angle of about 30 under a small load to properlyseat the spherical block, but take
19、care not to move the specimenout of the central position. Preferably, the rate of loadingshould not exceed 100 psi (690 kPa)/s, but this requirementmay be considered as being met if the speed of the loadinghead is not more than 0.05 in. (1.3 mm)/min.10. Calculation10.1 Calculate the compressive stre
20、ngth of each specimenas follows:C 5 W/A (1)where:C = compressive strength of the specimen, psi (MPa)W = 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 Report the av
21、erage of all values of compressivestrength of specimens loaded perpendicular to the bedding (orrift) as shown in Fig. 1(a) in a dry condition as the compressivestrength perpendicular to the rift in a dry condition. Similarlyreport the values perpendicular/wet, parallel/dry as shown inFig. 1(b) and p
22、arallel/wet. All determinations shall be reportedas information.11.2 The following additional information shall be reported:11.2.1 Identification of the sample, including name andlocation of the quarry, name or position of the ledge, date whensample was taken and trade name or grade of stone,11.2.2
23、Size and shape of specimens used in the tests, and11.2.3 A description of the way in which the specimenswere prepared.12. Precision and Bias12.1 Individual variations in a natural product may result indeviation from accepted values. A precision section will beadded when sufficient data are available
24、 to indicate acceptabletolerances in repeatability and reproducibility.EXPLANATORY NOTESNOTE 1For very coarse-grain materials like some of the granites, thediameter of the specimen should not be less than 2.5 in. (63.5 mm).NOTE 2The height of the specimen is considered as the distancebetween the loa
25、d-bearing faces.NOTE 3In some materials, such as granite, three directions withrespect to fissility are recognized, as follows: “rift” (the plane of easiestsplitting), “grain” (the plane of next easiest splitting), and “head-grain”(the plane of hardest splitting). Occasionally, tests are required fo
26、rdetermining the strength perpendicular to each of these directions. In suchcases, the sample shall be marked at the quarry to show which faces aregrain, rift, and head-grain, and the required number of specimens shall beprepared with load-bearing faces parallel to each of these planes andproperly l
27、abeled for the various tests.NOTE 4Accuracy of test results depends largely on uniform distribu-tion of the load over the bearing faces. In order to grind the surfaces toreasonably true planes, considerable care is necessary. The followingprocedure is suggested: Assuming that the specimen is a cube
28、or cylinderand the load is to be applied to the ends, mark two adjacent sides forreference, then grind the ends on a grinding wheel or lap until they areperpendicular to these reference sides as gaged by a try square. Completethe grinding by rubbing the ends on a smooth machine-planed surface ofa ca
29、st iron plate with No. 80 emery and water. The specimen should begrasped as near the surface of the plate as possible to prevent rocking ofthe specimen. A suitable way to determine when the surfaces arereasonably plane is to dip the specimen in water and press the ends on asmooth machine-planed and
30、polished surface of a 10-lb (4.5-kg) weight.If the weight can be lifted by raising the specimen, the surfaces may beconsidered to be sufficiently accurate. A satisfactory mechanical means offinishing the bearing surfaces of the specimens is to place them in a chuckin a lathe and surface the ends wit
31、h a tool post grinder. This grinderconsists of a small motor and arbor carrying an abrasive wheel which turnsat about 5000 rpm. A three-point chuck is used to permit the surfacing ofcylindrical, square prism, or cubical specimens. When the square-typeNOTE 1Dashed lines indicate direction of bedding
32、or rift. Arrows indicate direction of loading.(a) Loading Perpendicular to Bedding or Rift (b) Loading Parallel to Bedding or RiftFIG. 1 Methods of Applying Load with Reference to Bedding or RiftC170062specimen is used it will be necessary to place a small piece of notchedmetal between the specimen
33、and one chuck point. This causes thespecimen to be placed somewhat off-center but does not interfere with thesurfacing process. The surface can be tested for planeness by holding astraightedge on the surface and viewing it before a strong light. Specimensfinished in this way commonly give considerab
34、ly higher test results thanspecimens prepared by hand.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 r
35、ights, 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 and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either f
36、or 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 heari
37、ng you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C170063
