1、Designation: D 4543 08Standard Practices forPreparing Rock Core as Cylindrical Test Specimens andVerifying Conformance to Dimensional and ShapeTolerances1This standard is issued under the fixed designation D 4543; the number immediately following the designation indicates the year oforiginal adoptio
2、n or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These practices specify procedures for laboratory rockcore test specimen
3、preparation of rock core from drill core andblock samples for strength and deformation testing and fordetermining the conformance of the test specimen dimensionswith tolerances established by this practice. Cubical, rectangu-lar, or other shapes are not covered by this practice. However,some of the
4、information contained with in this practice and instandard Test Method C 170 may still be of use to preparingother test specimen shapes.1.2 Rock is a complex engineering material that can varygreatly as a function of lithology, stress history, weathering,moisture content and chemistry, and other nat
5、ural geologicprocesses. As such, it is not always possible to obtain orprepare rock core specimens that satisfy the desirable toler-ances given in this practice. Most commonly, this situationpresents itself with weaker, more porous, and poorly cementedrock types and rock types containing significant
6、 or weak (orboth) structural features. For these and other rock types whichare difficult to prepare, all reasonable efforts shall be made toprepare a specimen in accordance with this practice and for theintended test procedure. However, when it has been determinedby trial that this is not possible,
7、prepare the rock specimen tothe closest tolerances practicable and consider this to be thebest effort (Note 1) and report it as such and if allowable ornecessary for the intended test, capping the ends of thespecimen as discussed in this practice is permitted.NOTE 1Best effort in surface preparation
8、 refers to the use of awell-maintained surface grinder, lathe or lapping machine by an experi-enced operator in which a reasonable number of attempts has been madeto meet the tolerances required in this procedure.1.3 This practices covers some, but not all of the curatorialissues that should be impl
9、emented. For curatorial issues thatshould be followed before and during specimen preparationrefer to Practices D 5079 and to the specific test standards insection 2.1 for which the specimens are being prepared.1.4 This practice also prescribes tolerance checks on thelength-to-diameter ratio, straigh
10、tness of the elements on thecylindrical surface, the flatness of the end bearing surfaces, andthe perpendicularity of the end surfaces with the axis of thecore.1.5 The requirement for specifying the moisture conditionof the test specimen is also stated. However, the requirementsin the specific test
11、standards in section 2.1 should be followedtoo.1.6 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D 6026, unless superseded by this standard.1.6.1 The practices/procedures used to specify how data arecollected/recorded and
12、 calculated in this standard are regardedas the industry standard. In addition, they are representative ofthe significant digits that generally should be retained. Theprocedures used do not consider material variation, purpose forobtaining the data, special purpose studies, or any consider-ations fo
13、r the users objectives; and it is common practice toincrease or reduce significant digits of reported data to becommensurate with these considerations. It is beyond the scopeof this standard to consider significant digits used in analysismethods for engineering design.1.7 UnitsThe dimensional values
14、 stated in either inch-pound units or SI units are to be regarded as standard, such as4 to 12 in. or 100 to 300 mm. The values stated in each systemmay not be exact equivalents; therefore, each system shall beused independently of the other. Combining values from the1These practices are under the ju
15、risdiction ofASTM Committee D18 on Soil andRock and are the direct responsibility of Subcommittee D18.12 on Rock Mechanics.Current edition approved Jan. 1, 2008. Published February 2008. Originallyapproved in 1985. Last previous edition approved in 2007 as D 4543 07.1*A Summary of Changes section ap
16、pears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.two systems may result in non-conformance with the standard.(Note, when mass measurements are added to determinedensities or unit weights, add the follo
17、wing.)1.7.1 Only the SI units are used for mass determinations,calculations and reported results. However, the use of balancesor scales recording pounds of mass (lbm) shall not be regardedas nonconformance with this standard.1.8 This standard does not purport to address all of thesafety concerns, if
18、 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 applica-bility of regulatory limitations prior to use.1.9 These practices offer a set of instructions for performingone or more specific operati
19、ons. This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgement. Not all aspects of this practicemay be applicable in all circumstances. This ASTM standard isnot intended to represent or replace the standard of care bywhich the adequacy of a give
20、n professional service must bejudged, nor should this document be applied without consid-eration of a projects many unique aspects. The word “stan-dard” in the title of this document means only that thedocument has been approved through the ASTM consensusprocess.2. Referenced Documents2.1 ASTM Stand
21、ards:2C 170 Test Method for Compressive Strength of DimensionStoneC 617 Practice for Capping Cylindrical Concrete Speci-mensD 653 Terminology Relating to Soil, Rock, and ContainedFluidsD2113 Practice for Rock Core Drilling and Sampling ofRock for Site InvestigationD 2216 Test Methods for Laboratory
22、Determination of Wa-ter (Moisture) Content of Soil and Rock by MassD 2936 Test Method for Direct Tensile Strength of IntactRock Core SpecimensD 3740 Practice for Minimum Requirements for AgenciesEngaged in the Testing and/or Inspection of Soil and Rockas Used in Engineering Design and ConstructionD
23、5079 Practices for Preserving and Transporting RockCore SamplesD 6026 Practice for Using Significant Digits in Geotechni-cal DataD 7012 Test Method for Compressive Strength and ElasticModuli of Intact Rock Core Specimens under VaryingStates of Stress and TemperaturesD 7070 Test Method for Creep of R
24、ock Core Under Con-stant Stress and Temperature3. Terminology3.1 For terminology used in this test method, refer toTerminology D 6534. Significance and Use4.1 The dimensional, shape, and surface tolerances of rockcore specimens are important for determining rock propertiesof intact specimens. This i
25、s especially true for strong rocks,greater than 7250 psi (50 MPa). Dimensional and surfacetolerance checks are required in the test methods listed inSection 2.1. To simplify test procedures in laboratories, theparts of those procedures that are common to the test methodsin Section 2.1 are given in t
26、his standard.4.2 This procedure is applicable to all the standards listed inSection 2.1. However, specimens for Test Method D 2936 donot need to be machined or to meet the specified tolerances forflatness and parallelism.4.3 The moisture condition of the specimen at the time ofthe sample preparation
27、 can have a significant effect upon thestrength and deformation characteristics of the rock. Goodpractice generally dictates that laboratory tests be made uponspecimens representative of field conditions. Thus, it followsthat the field moisture condition of the specimen should bepreserved until the
28、time of the test. In some instances, however,there may be reasons for testing specimens at other moisturecontents, from saturation to dry. In any case, the moisturecontent of the test specimen should be tailored to the problemat hand. Excess moisture will affect the adhesion of resistancestrain gage
29、s, if used, and the accuracy of their performance.Adhesives used to bond the rock to steel end pieces in thedirect tension test will also be affected adversely by excessmoisture.NOTE 2The quality of the result produced by these practices isdependent upon the competence of the personnel performing it
30、 and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D 3740 are generally considered capable of competentand objective testing and sampling. Users of these practices are cautionedthat compliance with Practice D 3740 does not in itself assure reliablere
31、sults. Reliable results depend on many factors; Practice D 3740 providesa means of evaluating some of those factors.5. Apparatus5.1 Support SurfaceA flat test surface which shall notdepart from a plane by more than 0.0005 in. (0.0013 mm) uponwhich the cylindrical sides of a rock core test specimen m
32、ay berolled and a V-block end of a rock core test specimen,displacement gage assembly, or both, is placed, the tolerance of. Machinist grade, certified, granite blocks are commonly usedfor support surfaces because they do not dent or rust. However,other materials may be used if they meet the criteri
33、a of theprocedure. The area of the support surface will depend on thesize of specimens to be prepared, however, a 12 in. 3 12 in.(300 mm 3 300 mm) area will be sufficient for most applica-tions.5.2 V-block (conformance tests)The V-block shall bemachinist quality with all bearing faces surfaces groun
34、d flat,smooth to within 0.0005 in. (13 m) and with a 90 includedangle. The V-block shall have some means of securing thespecimen firmly in the V-block. The dimensions of the V-block2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.or
35、g. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.D4543082must be such that it does not physically interfere with thedisplacement gage readings.5.3 Displacement Gage Assembly:5.3.1 Dial or Electronic Displacement GageThe sensitiv-
36、ity of the displacement gage shall be at least 0.001 in. (0.02mm) for measurement of cylindrical surfaces. The measure-ment contact tip of the displacement gage shall be round inshape. A displacement gage readable to 0.0001 in. (0.002 mm)is required for measurements on the end surfaces.5.3.2 Dial or
37、 Electronic Displacement gage StandAstandwith a base and vertically mounted rod with an adjustable gageholder to support the gage on the flat surface at the properheight for the specimen and to take measurements normal tothe flat surface. The side of the base can be machined flat sothat it may be us
38、ed as a straight edge for taking measurementsas shown in Fig. 1 and described in Section 9.1.5.4 Feeler Gage Set25 or 26 leaf/blade set; 3 in. long by in. wide, and thicknesses beginning at 0.015 in. and endingat 0.025 in. or 25 or 26 leaf/blade set; 75-76 mm long by12.7-15 mm wide, and thicknesses
39、beginning at 0.04 mm andending at 1.00 mm.5.5 Surface GrinderA manual or automatic machinistssurface grinder equipped with a grinding wheel suited for thespecimen, a magnetic flat surface and a special V-block to holdthe sample during the grinding process. The apparatus is alsoequipped to apply appr
40、opriate cooling and cutting agents (ifneeded) at the cutting surface to cool the grinding wheelsurface and wash away cuttings.5.6 V-Block (Grinder)A metal V-block for holding therock specimen in the surface grinder on the magnetic chuckand is configured so that the specimen can be rotated to grindbo
41、th ends without interfering with the grinding process.5.7 Diamond SawA rock saw equipped with a segmentedcircular diamond saw blade, with a moveable platform forholding and feeding the sample, perpendicular to the core axis,into the cutting surface of the blade. The moveable platformmay be a manual
42、or automatic feed. The apparatus is alsoequipped to apply appropriate cooling and cutting agents (ifneeded) at the cutting surface to cool the blade and wash awaycuttings.5.8 For Drilling Block Samples:5.8.1 A 10 horsepower drill, with a GFI (Ground FaultInterrupt) for electrical powered drills.5.8.
43、2 A thin walled diamond core barrel.5.8.3 A water swivel and adaptors for hooking up to thedrill.5.9 (Optional) Lapper.5.10 (Optional) Machinist Shaper.5.11 Machinist Calipers, or similar device, with vernier,digital, or dial readouts readable to 0.01 in. (0.25 mm) andlarge enough for the size of th
44、e specimens being measured.5.12 Miscellaneous Tools: machinist scribe and water proofmarkers.6. Samples6.1 Samples for preparing specimens can be either drillcores obtained directly from the in situ rock or obtained fromblock samples cored in the field or in the laboratory.6.2 Samples should be sele
45、cted or obtained (or both) to meetthe objectives of the specific standard listed in 2.1 and the testprogram and any requirements related to anisotropic propertiesof the in situ material that are relevant to the intended use.7. Specimens7.1 Test specimens shall be right circular cylinders withinthe t
46、olerances specified herein.7.2 The specimen shall have a length-to-diameter ratio(L/D) of 2.0 to 2.5 and a diameter of not less than 1-78 in. (47mm).7.2.1 The larger the internal friction angle of a specimen themore desirable it will be to have larger L/D ratios so that thespecimen can potentially d
47、evelop a true shear plane that doesnot pass through either end of the specimen or is not altered bythe specimen size.NOTE 3It is desirable that the diameter of rock test specimens be atleast ten times the diameter of the largest mineral grain. For weak rocktypes which behave more like soil (for exam
48、ple, weakly cementedsandstone), the specimen diameter should be at least six times themaximum particle diameter. It is considered that the specified minimumspecimen diameter of approximately 1-78 in. (47 mm) will satisfy thiscriterion in the majority of cases. When cores of diameter smaller than the
49、specified minimum must be tested because of the unavailability of largerdiameter core or prohibitive use of large drilling equipment (as is often thecase in the mining industry), costs, or both, and suitable notation of thisfact shall be made in the report.7.3 The cylindrical surfaces of the specimen shall be gen-erally smooth and free of abrupt irregularities, with all theFIG. 1 Assembly for Determining the Straightness of Elementson the Cylindrical Surface (S2)D4543083elements straight to within 0.020 in. (0.50 mm) over the fulllength of the specimen, as determi
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