ASTM D7248/D7248M-21

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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: D7248/D7248M − 12 (Reapproved 2017) D7248/D7248M − 21
Standard Test Method for
Bearing/Bypass High Bearing - Low Bypass Interaction
Response of Polymer Matrix Composite Laminates Using
1
2-Fastener Specimens
This standard is issued under the fixed designation D7248/D7248M; 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 This test method determines the uniaxial bearing/bypass interaction response of multi-directional polymer matrix composite
laminates reinforced by high-modulus fibers by either double-shear tensile loading (Procedures A and C) (Procedure A) or
single-shear tensile or compressive loading (Procedure B) of a two-fastener specimen. The scope of this test method is limited to
net section (bypass) failure modes. Standard specimen configurations using fixed values of test parameters are described for each
procedure. A number of test parameters may be varied within the scope of the standard, provided that the parameters are fully
documented in the test report. The composite material forms are limited to continuous-fiber or discontinuous-fiber (tape or fabric,
or both) reinforced composites for which the laminate is balanced and symmetric with respect to the test direction. The range of
acceptable test laminates and thicknesses are described in 8.2.1. Test methods for high bypass - low bearing response of polymer
matrix composite materials, previously published under Procedure C of this test method, are now published in Test Method
D8387/D8387M.
1.2 This test method is consistent with the recommendations of MIL-HDBK-17, Composite Materials Handbook, CMH-17, which
describes the desirable attributes of a bearing/bypass interaction response test method.
1.3 The two-fastener test configurations described in this test method are similar to those in Test Method D5961/D5961M as well
as those used by industry to investigate the bearing portion of the bearing/bypass interaction response for bolted joints, where the
specimen may produce either a bearing failure mode or a bypass failure mode. Should the test specimen fail in a bearing failure
mode rather than the desired bypass mode, then the test should be considered to be a bearing dominated bearing/bypass test, and
the data reduction and reporting procedures of Test Method D5961/D5961M should be used instead of those given in this
standard.test method.
1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in
each system mayare not benecessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be
used independently of the other. Combiningother, and values from the two systems may result in non-conformance with the
standard.shall not be combined.
1.4.1 Within the text, the inch-pound units are shown in brackets.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1
This test method is under the jurisdiction of ASTM Committee D30 on Composite Materials and is the direct responsibility of Subcommittee D30.05 on Structural Test
Methods.
Current edition approved Aug. 1, 2017May 15, 2021. Published May 2017June 2021. Originally approved in 2007. Last previous edition approved in 20122017 as
D7248/D7248MD7248/D7248M – 12-12.(2017). DOI: 10.1520/D7248_D7248M-12R17.10.1520/D7248_D7248M-21.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D7248/D7248M − 21
1.6 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D792 Test Methods for Density and Specific Gravity (Relative Density) of Plastics by Displacement
D883 Terminology Relating to Plastics
D2584 Test Method for
...

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D7248/D7248M − 21
Standard Test Method for
High Bearing - Low Bypass Interaction Response of
Polymer Matrix Composite Laminates Using 2-Fastener
1
Specimens
This standard is issued under the fixed designation D7248/D7248M; 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 reporting procedures of Test Method D5961/D5961M should
be used instead of those given in this test method.
1.1 This test method determines the uniaxial bearing/bypass
1.4 Units—The values stated in either SI units or inch-
interaction response of multi-directional polymer matrix com-
pound units are to be regarded separately as standard. The
posite laminates reinforced by high-modulus fibers by either
values stated in each system are not necessarily exact equiva-
double-shear tensile loading (Procedure A) or single-shear
lents; therefore, to ensure conformance with the standard, each
tensile or compressive loading (Procedure B) of a two-fastener
system shall be used independently of the other, and values
specimen. The scope of this test method is limited to net
section (bypass) failure modes. Standard specimen configura- from the two systems shall not be combined.
1.4.1 Within the text, the inch-pound units are shown in
tions using fixed values of test parameters are described for
each procedure. A number of test parameters may be varied brackets.
within the scope of the standard, provided that the parameters
1.5 This standard does not purport to address all of the
are fully documented in the test report. The composite material
safety concerns, if any, associated with its use. It is the
forms are limited to continuous-fiber or discontinuous-fiber
responsibility of the user of this standard to establish appro-
(tape or fabric, or both) reinforced composites for which the
priate safety, health, and environmental practices and deter-
laminate is balanced and symmetric with respect to the test
mine the applicability of regulatory limitations prior to use.
direction. The range of acceptable test laminates and thick-
1.6 This international standard was developed in accor-
nesses are described in 8.2.1. Test methods for high bypass -
dance with internationally recognized principles on standard-
low bearing response of polymer matrix composite materials,
ization established in the Decision on Principles for the
previously published under Procedure C of this test method,
Development of International Standards, Guides and Recom-
are now published in Test Method D8387/D8387M.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.2 This test method is consistent with the recommendations
of Composite Materials Handbook, CMH-17, which describes
2. Referenced Documents
the desirable attributes of a bearing/bypass interaction response
2
2.1 ASTM Standards:
test method.
D792 Test Methods for Density and Specific Gravity (Rela-
1.3 The two-fastener test configurations described in this
tive Density) of Plastics by Displacement
test method are similar to those in Test Method D5961/
D883 Terminology Relating to Plastics
D5961M as well as those used by industry to investigate the
D2584 Test Method for Ignition Loss of Cured Reinforced
bearing portion of the bearing/bypass interaction response for
Resins
bolted joints, where the specimen may produce either a bearing
D2734 Test Methods for Void Content of Reinforced Plastics
failure mode or a bypass failure mode. Should the test
D3171 Test Methods for Constituent Content of Composite
specimen fail in a bearing failure mode rather than the desired
Materials
bypass mode, then the test should be considered to be a bearing
D3878 Terminology for Composite Materials
dominated bearing/bypass test, and the data reduction and
D5229/D5229M Test Method for Moisture Absorption Prop-
erties and Equilibrium Conditioning of Polymer Matrix
Composite Materials
1
This test method is under the jurisdiction of ASTM Committee D30 on
Composite Materials and is the direct responsibility of Subcommittee D30.05 on
2
Structural Test Methods. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 15, 2021. Published June 2021. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 2007. Last previous edition approved in 2017 as D7248/ Standards volume information, refer to the standard’s Document Summary page on
D7248M – 12(2017). DOI: 10.1520/D7248_D7248M-21. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.
...