ASTM D7070-16
(Test Method)Standard Test Methods for Creep of Rock Core Under Constant Stress and Temperature
Standard Test Methods for Creep of Rock Core Under Constant Stress and Temperature
SIGNIFICANCE AND USE
5.1 There are many underground structures that are constructed for permanent or long-term use. Often, these structures are subjected to a relatively constant load. Creep tests provide quantitative parameters for stability analysis of these structures.
5.2 The deformation and strength properties of rock cores measured in the laboratory usually do not accurately reflect large-scale in situ properties, because the latter are strongly influenced by joints, faults, inhomogeneities, weakness planes, and other factors. Therefore, laboratory test results of intact specimens shall be utilized with proper judgment in engineering applications.
Note 1: The statements on precision and bias contained in this test method; the precision of this test method is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice D3740 does not in itself assure reliable testing. Reliable testing depends on many factors; Practice D3740 provides a means of evaluating some of these factors.
SCOPE
1.1 These test methods cover the creep behavior of intact weak and hard rock core in fixed states of stress at ambient (room) or elevated temperatures. For creep behavior at lower temperatures refer to Test Method D5520. The methods specify the apparatus, instrumentation, and procedures necessary to determine the strain as a function of time under sustained load at constant temperature and when applicable, constant humidity.
1.1.1 Hard rocks are considered those with a maximum axial strain at failure of less than 2 %. Weak rocks include such materials as salt, potash, shale, and weathered rock, which often exhibit very large strain at failure.
1.2 This standard consists of three methods that cover the creep capacity of core specimens.
1.2.1 Method A—Creep of Hard Rock Core Specimens in Uniaxial Compression at Ambient or Elevated Temperature.
1.2.2 Method B—Creep of Weak Rock Core Specimens in Uniaxial Compression at Ambient or Elevated Temperature.
1.2.3 Method C—Creep of Rock Core Specimens in Triaxial Compression at Ambient or Elevated Temperature.
1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.
1.4 The procedures used to specify how data are collected/recorded and calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering design.
1.5 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see Section 7.
General Information
Relations
Buy Standard
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: D7070 − 16
Standard Test Methods for
Creep of Rock Core Under Constant Stress and
1
Temperature
This standard is issued under the fixed designation D7070; 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* 1.5 Units—The values stated in SI units are to be regarded
asthestandard.Thevaluesgiveninparenthesesaremathemati-
1.1 These test methods cover the creep behavior of intact
cal conversions to inch-pound units that are provided for
weak and hard rock core in fixed states of stress at ambient
information only and are not considered standard.
(room) or elevated temperatures. For creep behavior at lower
1.6 This standard does not purport to address all of the
temperaturesrefertoTestMethodD5520.Themethodsspecify
safety concerns, if any, associated with its use. It is the
the apparatus, instrumentation, and procedures necessary to
responsibility of the user of this standard to establish appro-
determine the strain as a function of time under sustained load
priate safety and health practices and to determine the
at constant temperature and when applicable, constant humid-
applicability of regulatory limitations prior to use. For specific
ity.
precautionary statements, see Section 7.
1.1.1 Hard rocks are considered those with a maximum
axialstrainatfailureoflessthan2%.Weakrocksincludesuch
2. Referenced Documents
materials as salt, potash, shale, and weathered rock, which
2
2.1 ASTM Standards:
often exhibit very large strain at failure.
D653Terminology Relating to Soil, Rock, and Contained
1.2 This standard consists of three methods that cover the
Fluids
creep capacity of core specimens.
D2113Practice for Rock Core Drilling and Sampling of
1.2.1 Method A—Creep of Hard Rock Core Specimens in
Rock for Site Exploration
Uniaxial Compression at Ambient or Elevated Temperature.
D2216Test Methods for Laboratory Determination ofWater
1.2.2 Method B—Creep of Weak Rock Core Specimens in
(Moisture) Content of Soil and Rock by Mass
Uniaxial Compression at Ambient or Elevated Temperature.
D2845Test Method for Laboratory Determination of Pulse
1.2.3 Method C—CreepofRockCoreSpecimensinTriaxial
Velocities and Ultrasonic Elastic Constants of Rock
Compression at Ambient or Elevated Temperature.
D3740Practice for Minimum Requirements for Agencies
1.3 All observed and calculated values shall conform to the
Engaged in Testing and/or Inspection of Soil and Rock as
guidelines for significant digits and rounding established in
Used in Engineering Design and Construction
Practice D6026.
D4543PracticesforPreparingRockCoreasCylindricalTest
Specimens and Verifying Conformance to Dimensional
1.4 The procedures used to specify how data are collected/
and Shape Tolerances
recorded and calculated in this standard are regarded as the
D5079Practices for Preserving andTransporting Rock Core
industry standard. In addition, they are representative of the
Samples
significant digits that generally should be retained. The proce-
D5520Test Method for Laboratory Determination of Creep
dures used do not consider material variation, purpose for
Properties of Frozen Soil Samples by Uniaxial Compres-
obtaining data, special purpose studies, or any considerations
sion
for the user’s objectives; and it is common practice to increase
D6026Practice for Using Significant Digits in Geotechnical
or reduce significant digits of reported data to commensurate
Data
with these considerations. It is beyond the scope of these test
E4Practices for Force Verification of Testing Machines
methodstoconsidersignificantdigitsusedinanalysismethods
E122PracticeforCalculatingSampleSizetoEstimate,With
for engineering design.
Specified Precision, the Average for a Characteristic of a
Lot or Process
1
This test method is under the jurisdiction ofASTM Committee D18 and is the
2
direct responsibility of Subcommittee D18.12 on Rock Mechanics. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Nov. 1, 2016. Published November 2016. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 2004. Last previous edition approved in 2008 as D7070-08. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D7070-16. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United
...
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 made to the previous version. Because
it 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 version
of the standard as published by ASTM is to be considered the official document.
Designation: D7070 − 08 D7070 − 16
Standard Test Methods for
Creep of Rock Core Under Constant Stress and
1
Temperature
This standard is issued under the fixed designation D7070; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 These test methods cover the creep behavior of intact softweak and hard rock core in fixed states of stress and temperature.
They at ambient (room) or elevated temperatures. For creep behavior at lower temperatures refer to Test Method D5520. The
methods specify the apparatus, instrumentation, and procedures for determining necessary to determine the strain as a function of
time under sustained load. Hard rocks are those with a maximum axial strain at failure of less than 2 %. Soft rocks include such
materials as salt and potash, which often exhibit very large strain at failure.load at constant temperature and when applicable,
constant humidity.
1.1.1 Hard rocks are considered those with a maximum axial strain at failure of less than 2 %. Weak rocks include such materials
as salt, potash, shale, and weathered rock, which often exhibit very large strain at failure.
1.2 This standard replaces and combines the following Standard Test Methods now to be referred to as Methods: consists of
three methods that cover the creep capacity of core specimens.
Method ‘A’ (D5341 Creep of Hard Rock Core Specimens in Uniaxial Compression at Ambient/Elevated Temperatures);
Method ‘B’ (D4405 Creep of Soft Rock Core Specimens in Uniaxial Compression at Ambient or Elevated Temperature); and
Method ‘C’ (D4406 Creep of Rock Core Specimens in Triaxial Compression at Ambient or Elevated Temperature).
1.2.1 Method A—Creep of Hard Rock Core Specimens in Uniaxial Compression at Ambient or Elevated Temperature.
1.2.2 Method B—Creep of Weak Rock Core Specimens in Uniaxial Compression at Ambient or Elevated Temperature.
1.2.3 Method C—Creep of Rock Core Specimens in Triaxial Compression at Ambient or Elevated Temperature.
1.3 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice
D6026.
1.3.1 The method used to specify how data are collected, calculated, or recorded in this standard is not directly related to the
accuracy to which the data can be applied in design or other uses, or both. How one applies the results obtained using this standard
is beyond its scope.
1.4 The procedures used to specify how data are collected/recorded and calculated in this standard are regarded as the industry
standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not
consider material variation, purpose for obtaining data, special purpose studies, or any considerations for the user’s objectives; and
it is common practice to increase or reduce significant digits of reported data to commensurate with these considerations. It is
beyond the scope of these test methods to consider significant digits used in analysis methods for engineering design.
1.5 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are mathematical
conversions to inch-pound units that are provided for information only and are not considered standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory
limitations prior to use. For specific precautionary statements, see Section 7.
2. Referenced Documents
2
2.1 ASTM Standards:
D653 Terminology Relating to Soil, Rock, and Contained Fluids
1
This test method is under the jurisdiction of ASTM Committee D18 and is the direct responsibility of Subcommittee D18.12 on Rock Mechanics.
Current edition approved July 1, 2008Nov. 1, 2016. Published August 2008November 2016. Originally approved in 2004. Last previous edition approved in 20042008
as D7070 – 04.D7070 - 08. DOI: 10.1520/D7070-08.10.1520/D7070-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the AST
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.