ASTM D5873-00(2005)e1
(Test Method)Standard Test Method for Determination of Rock Hardness by Rebound Hammer Method
Standard Test Method for Determination of Rock Hardness by Rebound Hammer Method
SCOPE
1.1 This test method covers the testing apparatus, sampling, test specimen preparation, and testing procedures for determining the rebound hardness number of rock material using a spring-driven steel hammer, referred to variously as a rebound hammer, impact test hammer, or concrete test hammer.
1.2 This test method is best suited for rock material with uniaxial compressive strengths (see Test Method D 7012) ranging between approximately 1 and 100 MPa.
1.3 The portable testing apparatus may be used in the laboratory or field to provide a means of rapid assessment of rock hardness or to serve as an indicator of rock hardness.
1.4 The values stated in SI units are to be regarded as the standard.
1.5 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 determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
e1
Designation:D5873–00 (Reapproved 2005)
Standard Test Method for
Determination of Rock Hardness by Rebound Hammer
Method
This standard is issued under the fixed designation D 5873; 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 (e) indicates an editorial change since the last revision or reapproval.
e NOTE—Editorial corrections were made in June 2005.
1. Scope* D 4543 Practice for Preparing Rock Core Specimens and
Determining Dimensional and Shape Tolerances
1.1 This test method covers the testing apparatus, sampling,
D 4879 Guide for Geotechnical Mapping of Large Under-
test specimen preparation, and testing procedures for determin-
ground Openings in Rock
ing the rebound hardness number of rock material using a
D 7012 Test Test Method for Compressive Strength and
spring-driven steel hammer, referred to variously as a rebound
Elastic Moduli of Intact Rock Core Specimens under
hammer, impact test hammer, or concrete test hammer.
Varying States of Stress and Temperatures
1.2 This test method is best suited for rock material with
2.2 ISRM Standards:
uniaxial compressive strengths (see Test Method D 7012)
Suggested Method for Determination of Schmidt Rebound
ranging between approximately 1 and 100 MPa.
Hardness
1.3 The portable testing apparatus may be used in the
Suggested Method for Quantitative Description of Discon-
laboratory or field to provide a means of rapid assessment of
tinuities in Rock Masses
rock hardness or to serve as an indicator of rock hardness.
1.4 The values stated in SI units are to be regarded as the
3. Terminology
standard.
3.1 For common definitions of terms in this standard, refer
1.5 This standard does not purport to address all of the
to Terminology D 653.
safety concerns, if any, associated with its use. It is the
3.2 Definitions of Terms Specific to This Standard:
responsibility of the user of this standard to establish appro-
3.2.1 rebound hammer—a portable, spring loaded, piston-
priate safety and health practices and determine the applica-
type, steel hammer used to classify the hardness of rock in the
bility of regulatory limitations prior to use.
field or laboratory.
2. Referenced Documents 3.2.2 rebound hardness number—H ,adimensionlessnum-
R
2 ber representing empirically determined, relative hardness of
2.1 ASTM Standards:
rock material or other hard substance by use of a rebound
C 805 Test Method for Rebound Number of Hardened
hammer.
Concrete
D 420 Guide to Site Characterization for Engineering, De-
4. Significance and Use
sign, and Construction Purposes
4.1 The rebound hardness method provides a means for
D 653 Terminology Relating to Rock, Soil, and Contained
rapid classification of the hardness of rock during site charac-
Fluids
terization for engineering, design, and construction purposes
D 3740 Practice for Minimum Requirements for Agencies
(seeGuideD 420),geotechnicalmappingoflargeunderground
Engaged in the Testing and/or Inspection of Soil and Rock
openings in rock (see Guide D 4879), or reporting the physical
as Used in Engineering Design and Construction
description of rock core (see Practice D 4543). The rebound
hardness number, H , can serve in a variety of engineering
r
applications that require characterization of rock material.
ThistestmethodisunderthejurisdictionofASTMCommitteeD18onSoiland
These applications include, for examples, the prediction of
Rock and is the direct responsibility of Subcommittee D18.12 on Rock Mechanics.
penetration rates for tunnel boring machines, determination of
Current edition approved May 1, 2005. Published June 2005. Originally
approved in 1995. Last previous edition approved in 2000 as D 5873 – 95(2000).
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 Brown, E. T., ed., Suggested Methods: Rock Characterization, Testing, and
Standards volume information, refer to the standard’s Document Summary page on Monitoring, International Society of Rock Mechanics: Pergamon Press, London,
the ASTM website. 1981.
*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 States.
e1
D5873–00 (2005)
rock quality for construction purposes, and prediction of 7. Specimen Preparation
hydraulic erodibility of rock.
7.1 For a block or core specimen, determine its length by
4.2 This test method is of limited use on very soft rock or
taking the average of four lengths measured at four equally
very hard rock (unconfined compressive strengths less than
spaced points on the circumference and record to the nearest 5
approximately 1 MPa or greater than 100 MPa).
mm.
4.3 The results of this test method are not intended for
7.2 For a block or core specimen, determine its diameter by
conversion to strength data suitable for design.
takingtheaverageoftwodiametersmeasuredatrightanglesto
each other approximately midway along the length of the
NOTE 1—Several types of rebound hammers are commercially avail-
specimen and record to the nearest 5 mm.
able to accommodate testing of various sizes and types of concrete
7.3 Report the moisture condition of the block or specimen.
construction (See Test Method C 805) and rock material.
7.4 Thetestsurfaceofallspecimens,eitherinthelaboratory
NOTE 2—The quality of the result produced by this standard is
dependent on the competence of the personnel performing it, and the or in the field, shall be smooth to the touch and free of joints,
suitability of the equipment and facilities used. Agencies that meet the
fractures, or other obvious localized discontinuities to a depth
criteria of Practice D 3740 are generally considered capable of competent
of at least 6 cm. In situ rock shall be flat and free of surface grit
and objective testing and sampling. Users of this standard are cautioned
over the area covered by the plunger. If the surface of the test
that compliance with Practice D 3740 does not in itself assure reliable
areaisheavilytextured,grinditsmoothwiththeabrasivestone
results.Reliableresultsdependonmanyfactors;PracticeD 3740provides
described in 5.4.
a means of evaluating some of those factors.
5. Apparatus 8. Calibration
8.1 Prior to each testing sequence, calibrate the hammer
5.1 Rebound Hammer, consisting of a spring-loaded piston,
using a calibration test anvil supplied by the manufacturer for
or hammer, which is projected against a metal anvil in contact
that purpose.
withtherocksurface.Thehammermusttravelwithafixedand
reproducible velocity. The rebound distance of the piston from 8.1.1 Place the calibration anvil in the core holder and
conduct ten readings on the anvil.
the steel plunger is measured in a linear scale attached to the
frameoftheinstrumentandistakenasanempiricalmeasureof 8.1.2 Calculate the correction factor by dividing the manu-
facturer’s standard hardness value for the anvil by the average
rock hardness.
of the ten readings taken on the anvil.
5.2 Steel Base—A steel base of minimum mass of 20 kg to
which specimens are securely fastened. Rock core specimens
NOTE 3—If the instrument reads lower than the manufacturer’s stan-
may be tested in a steel cradle with a semicylindrical machined
dard hardness value, the correction factor will be greater than unity. If the
slot of the same radius as the core, or firmly seated in a steel
readings are higher, the correction factor will be less than unity.
V-block.
NOTE 4—Operation of the rebound hammer is satisfactory if the
calibration readings fall within the range provided by the manufacturer. If
5.3 Calibration Anvil—The standard calibration block used
the calibration readings fall outside this range, the instrument must be
to calibrate the rebound hammer.
cleaned, adjusted, or returned to the manufacturer for correction.
5.4 Abrasive Stone—A medium-grained texture silicon car-
NOTE
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.