ASTM D4543-19
(Practice)Standard Practices for Preparing Rock Core as Cylindrical Test Specimens and Verifying Conformance to Dimensional and Shape Tolerances
Standard Practices for Preparing Rock Core as Cylindrical Test Specimens and Verifying Conformance to Dimensional and Shape Tolerances
SIGNIFICANCE AND USE
4.1 The dimensional, shape, and surface tolerances of rock core test specimens are important for determining rock properties of intact specimens. This is especially true for strong rocks, greater than 7250 psi (50 MPa) and for rock specimens that will be tested in stiff testing load frames without a spherical seat where non-uniform loading could occur. Dimensional and surface tolerance checks are required in the test methods listed in Section 2.1. To simplify test procedures in laboratories, the parts of those procedures that are common to the test methods in Section 2.1 are given in this standard.
4.2 This procedure is applicable to all the standards listed in Section 2.1; however, specimens for Test Method D2936 do not need to be machined or to meet the specified tolerances for flatness and parallelism.
4.3 The moisture condition of the specimen at the time of the sample preparation can have a significant effect upon the strength and deformation characteristics of the rock. Good practice generally dictates that laboratory tests be made upon a specimens’ representative of field conditions. Thus, it follows that the field moisture condition of the specimen should be preserved until the time of the test. In some instances, however, there may be reasons for testing specimens at other moisture contents, from saturation to dry. In any case, the moisture content of the test specimen should be tailored to the problem at hand.
Note 3: Discussions on moisture content are common in many rock testing standards but professional judgement will be needed to both handle and report this issue. For example, when obtaining the samples or preparing the specimens, water or some other cooling agent may be required or used. Therefore, the moisture in the specimen or samples may not be what it was in situ; this applies to both water chemistry and quantity of fluids. This issue should be addressed, and a plan put in place for each step from the sampling to the testing phase in a ...
SCOPE
1.1 These practices specify procedures for preparing rock test specimen of rock core from drill core obtained in the field or from block samples for strength and deformation testing and for determining the conformance of the test specimen dimensions with tolerances established by this practice. Cubical, rectangular, or other shapes are not covered by this practice. However, some of the information contained within this practice and in standard Test Method C170 may still be of use to preparing other test specimen shapes.
1.2 Rock is a complex engineering material that can vary greatly as a function of lithology, stress history, weathering, moisture content and chemistry, and other natural geologic processes. As such, it is not always possible to obtain or prepare rock core specimens that satisfy the desirable tolerances given in this practice. Most commonly, this situation presents itself with weaker, more porous, and poorly cemented rock types and rock types containing significant or weak (or both) structural features. For rock types which are difficult to prepare, all reasonable efforts should be made to prepare a specimen in accordance with this practice and for the intended test procedure. However, when it has been determined by trial and error that this is not possible, prepare the rock specimen to the closest tolerances practicable and consider this to be the best effort (Note 1) and report it as such and if allowable or necessary for the intended test, capping the ends of the specimen as discussed in this practice is permitted.
Note 1: Best effort in surface preparation refers to the use of a well-maintained, suitable surface grinder, lathe or lapping machine and any required ancillary equipment are utilized by an experienced operator and in which a reasonable number of attempts has been made to meet the tolerances required in this procedure.
1.3 This practices covers some, but not all of the curatorial iss...
General Information
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Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D4543 − 19
Standard Practices for
Preparing Rock Core as Cylindrical Test Specimens and
Verifying Conformance to Dimensional and Shape
1
Tolerances
This standard is issued under the fixed designation D4543; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* refertoPracticesD5079andtothespecificteststandardsin2.1
for which the specimens are being prepared.
1.1 These practices specify procedures for preparing rock
test specimen of rock core from drill core obtained in the field 1.4 This practice also prescribes tolerance checks on the
orfromblocksamplesforstrengthanddeformationtestingand length-to-diameter ratio, straightness of the elements on the
for determining the conformance of the test specimen dimen- cylindricalsurface,theflatnessoftheendbearingsurfaces,and
sions with tolerances established by this practice. Cubical, the perpendicularity of the end surfaces with the axis of the
rectangular, or other shapes are not covered by this practice. core.
However, some of the information contained within this
NOTE 2—This practice does not purport to cover all the issues that will
practice and in standard Test Method C170 may still be of use
or could be encountered that may control the quality of the specimen
to preparing other test specimen shapes.
preparation required. Each laboratory may have their own issues, espe-
cially for different compression load frames or rock types. For example,
1.2 Rock is a complex engineering material that can vary
stiff testing frames versus traditional load frames and loading platens with
greatly as a function of lithology, stress history, weathering,
or without spherical seating. Specimens for a stiff testing load frame with
moisture content and chemistry, and other natural geologic nosphericalseatmayneedtohavemorestringentrequirementsdepending
on the type of rock being tested. This procedure has tried to show the
processes. As such, it is not always possible to obtain or
methods and QA that may be involved while keeping in mind those
prepare rock core specimens that satisfy the desirable toler-
materials that are difficult to work with and for which the specimens will
ances given in this practice. Most commonly, this situation
still be suitable to be tested. The available literature and input on this
presents itself with weaker, more porous, and poorly cemented
subject from D18.12 members were considered as much as possible for
2
rock types and rock types containing significant or weak (or this standard.
both) structural features. For rock types which are difficult to
1.5 The requirement for specifying the moisture condition
prepare, all reasonable efforts should be made to prepare a
and volume of the test specimen is also stated. However, the
specimen in accordance with this practice and for the intended
requirements in the specific test standards in 2.1 should be
test procedure. However, when it has been determined by trial
followed too.
and error that this is not possible, prepare the rock specimen to
1.6 All observed and calculated values shall conform to the
the closest tolerances practicable and consider this to be the
guidelines for significant digits and rounding established in
best effort (Note 1) and report it as such and if allowable or
Practice D6026, unless superseded by this standard.
necessary for the intended test, capping the ends of the
1.6.1 The practices/procedures used to specify how data are
specimen as discussed in this practice is permitted.
collected/recorded and calculated in this standard are regarded
NOTE 1—Best effort in surface preparation refers to the use of a
as the industry standard. In addition, they are representative of
well-maintained, suitable surface grinder, lathe or lapping machine and
the significant digits that generally should be retained. The
any required ancillary equipment are utilized by an experienced operator
proceduresuseddonotconsidermaterialvariation,purposefor
and in which a reasonable number of attempts has been made to meet the
obtaining the data, special purpose studies, or any consider-
tolerances required in this procedure.
ations for the user’s objectives; and it is common practice to
1.3 This practices covers some, but not all of the curatorial
increase or reduce significant digits of reported data to be
issues that should be implemented. For curatorial issues that
commensuratewiththeseconsiderations.Itisbeyondthescope
should be followed before
...
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