ASTM D7565/D7565M-09
(Test Method)Standard Test Method for Determining Tensile Properties of Fiber Reinforced Polymer Matrix Composites Used for Strengthening of Civil Structures
Standard Test Method for Determining Tensile Properties of Fiber Reinforced Polymer Matrix Composites Used for Strengthening of Civil Structures
SIGNIFICANCE AND USE
This test method can be used to obtain the tensile force capacity and ultimate tensile strain of FRP material used for the strengthening of other structural materials such as, metals, timber, and reinforced concrete. The principal test variables could be the FRP constituents and fabrication method or the size or type of FRP laminate. The obtained tensile properties can be used for material specifications, quality control and assurance, structural design and analysis, and research and development. The stress, strength, and modulus of elasticity can be calculated using either the gross composite area method or the effective fiber area method.
This test method focuses on the FRP material itself, irrespective of the gripping method. Therefore, maximum force and strain data associated with failure or pullout at either grip are disregarded. The force capacity and maximum strain measurements are based solely on test specimens that fail in the gauge section.
SCOPE
1.1 This test method describes the requirements for sample preparation, tensile testing, and results calculation of flat fiber reinforced polymer (FRP) composite materials used for the strengthening of structures made of materials such as metals, timber, masonry, and reinforced concrete. The method may be used to determine the tensile properties of wet lay-up and pre-impregnated FRP composites fabricated on site or manufactured in a factory setting. The FRP composite may be of either unidirectional (0-degrees) or cross-ply (0/90 type) reinforcement. For cross-ply laminates, the construction may be achieved using multiple-layers of unidirectional fibers at either 0 or 90 degrees, or one or more layers of stitched or woven 0/90 fabrics. The composite material forms are limited to continuous fiber or discontinuous fiber-reinforced composites in which the laminate is balanced and symmetric with respect to the test direction. The method only covers the determination of the tensile properties of the FRP composite material. Other components used to attach the FRP material to the substrate, such as the primer, putty, and adhesive in externally bonded strengthening systems, are excluded from the sample preparation and testing detailed in this document. This test method refers to Test Method D3039/D3039M for conduct of the tests.
1.2 The values stated in either SI units or inch-pound units are to be regarded as standard. Within the text, the inch-pound units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.
1.3 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.
Designation:D7565/D7565M–09
Standard Test Method for
Determining Tensile Properties of Fiber Reinforced Polymer
Matrix Composites Used for Strengthening of Civil
Structures
This standard is issued under the fixed designation D7565/D7565M; 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 2. Referenced Documents
1.1 This test method describes the requirements for sample 2.1 ASTM Standards:
preparation, tensile testing, and results calculation of flat fiber D883 Terminology Relating to Plastics
reinforced polymer (FRP) composite materials used for the D3039/D3039M Test Method for Tensile Properties of
strengthening of structures made of materials such as metals, Polymer Matrix Composite Materials
timber, masonry, and reinforced concrete. The method may be D3878 Terminology for Composite Materials
used to determine the tensile properties of wet lay-up and D5229/D5229M Test Method for Moisture Absorption
pre-impregnated FRP composites fabricated on site or manu- Properties and Equilibrium Conditioning of Polymer Ma-
factured in a factory setting. The FRP composite may be of trix Composite Materials
either unidirectional (0-degrees) or cross-ply (0/90 type) rein- D5687/D5687M Guide for Preparation of Flat Composite
forcement. For cross-ply laminates, the construction may be Panels with Processing Guidelines for Specimen Prepara-
achieved using multiple-layers of unidirectional fibers at either tion
0 or 90 degrees, or one or more layers of stitched or woven E6 TerminologyRelatingtoMethodsofMechanicalTesting
0/90 fabrics. The composite material forms are limited to E122 Practice for Calculating Sample Size to Estimate,
continuous fiber or discontinuous fiber-reinforced composites With Specified Precision, the Average for a Characteristic
in which the laminate is balanced and symmetric with respect of a Lot or Process
tothetestdirection.Themethodonlycoversthedetermination E177 Practice for Use of the Terms Precision and Bias in
of the tensile properties of the FRP composite material. Other ASTM Test Methods
components used to attach the FRP material to the substrate, E456 Terminology Relating to Quality and Statistics
such as the primer, putty, and adhesive in externally bonded
3. Terminology
strengthening systems, are excluded from the sample prepara-
3.1 Definitions—Terminology D3878 defines terms relating
tion and testing detailed in this document. This test method
refers toTest Method D3039/D3039M for conduct of the tests. to high-modulus fibers and their composites. Terminology
D883definestermsrelatingtoplastics.TerminologyE6defines
1.2 The values stated in either SI units or inch-pound units
are to be regarded as standard. Within the text, the inch-pound terms relating to mechanical testing. Terminology E456 and
E177 define terms relating to statistics. In the event of a
units are shown in brackets. The values stated in each system
are not exact equivalents; therefore, each system must be used conflict between terms, Terminology D3878 shall have prece-
dence over the other standards.
independently of the other. Combining values from the two
systems may result in nonconformance with the standard. 3.2 Definitions of Terms Specific to This Standard:
3.2.1 screed, v—to move a flat rule along the top of a
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the saturated laminate to level the top of the laminate and
simultaneously remove excess resin.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- 3.2.2 shop-manufactured FRP composite, n—an FRP com-
positematerialmanufacturedundercontrolledconditionsusing
bility of regulatory limitations prior to use.
an automated process in a factory, typically with tight control
This test method is under the jurisdiction of ASTM Committee D30 on
Composite Materials and is the direct responsibility of Subcommittee D30.05 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Structural Test Methods. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Current edition approved Nov. 1, 2009. Published January 2010. DOI: 10.1520/ Standards volume information, refer to the standard’s Document Summary page on
D7565_D7565M-09. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D7565/D7565M–09
over the volume fractions and alignment of fibers, matrix, and can be used for material specifications, quality control and
voids in the material as well as the cross-sectional geometry. assurance, structural design and analysis, and research and
For strengthening applications, shop-manufactured FRP com- development. The stress, strength, and modulus of elasticity
posites are typically bonded to the substrate subsequent to the canbecalculatedusingeitherthegrosscompositeareamethod
fabrication of the composite reinforcement. or the effective fiber area method.
3.2.3 wet lay-up FRP composite, n—an FRP composite 5.2 This test method focuses on the FRP material itself,
material fabricated by manually impregnating dry fibers with a irrespectiveofthegrippingmethod.Therefore,maximumforce
matrix of polymeric resin. Semi-automated processes such as and strain data associated with failure or pullout at either grip
machine-aidedwettingoffabricsbeforeplacementorvacuum- are disregarded. The force capacity and maximum strain
aidedimpregnationoflaminatesafterplacementareconsidered measurementsarebasedsolelyontestspecimensthatfailinthe
part of wet lay-up FRP. For civil infrastructure strengthening gauge section.
applications,thedegreeofcontroloverthevolumefractionsof
6. Interferences
fibers, matrix, and voids as well as the overall cross-sectional
geometry in wet lay-up FRP composites may be less than that 6.1 A summary of the interferences, specifically material
for shop-manufactured composites on account of the manual
and specimen preparation, gripping, system alignment, and
process. For strengthening applications, wet lay-up FRP com-
edge effects are presented in D3039/D3039M.
posites are typically applied to the substrate at the same time
6.2 Additional interferences may arise from lack of control
thedryfiberisimpregnated.Theimpregnatingresinactsasthe
in wet lay-up specimen preparation procedures outlined in
saturant for the FRP composite and as the bonding agent
8.3.1. Specimen variations in resin content, ply thickness, void
between the composite reinforcement and the substrate. Wet
content and degree of cure may contribute to variability in test
lay-up specimens may be fabricated in either a field or a
results.
laboratory setting.
7. Apparatus
3.3 Symbols:
3.3.1 CV—sample coefficient of variation.
7.1 Requirements for testing machines and instrumentation
*
3.3.2 F —force carrying capacity of FRP laminate per unit
are the same as those given in D3039/D3039M, Section 7.
width.
*
8. Sampling and Test Specimens
3.3.3 K —stiffness of FRP laminate per unit width.
3.3.4 L —extensometer gage length.
g
8.1 Sampling—Test at least five specimens per test condi-
3.3.5 n—number of specimens.
tionunlessvalidresultscanbegainedthroughtheuseoffewer
3.3.6 P—force carried by test coupon.
specimens, such as in the case of a designed experiment. For
max
3.3.7 P —maximum tensile force.
statisticallysignificantdata,theproceduresoutlinedinPractice
3.3.8 s —sample standard deviation.
n−1
E122 should be consulted. Report the method of sampling.
3.3.9 w—coupon width.
NOTE 1—If specimens are to undergo environmental conditioning to
3.3.10 x—test result for an individual coupon from the
I
equilibrium, and are of such type or geometry that the weight change of
sample population for a given property.
the material cannot be properly measured by weighing the specimen itself
3.3.11 x¯—mean or average (estimate of mean) of a sample
(suchasatabbedmechanicalcoupon),thenuseanothertravelercouponof
population for a given property.
the size (but without tabs) to determine when equilibrium has been
3.3.12 s—normal stress. reached for the specimens being conditioned.
8.2 Geometry—Variation in specimen width should be no
4. Summary of Test Method
greater than 61%. Specimens width should be determined per
4.1 Flat FRP specimens are prepared using a wet lay-up
Test Method D3039/D3039M, Section 7.1. Other dimensions
fabrication procedure or cut from a shop-manufactured lami-
shall conform to Test Method D3039/D3039M Section 8.2.1
nate.Fortestingpurposes,wetlay-upmaterialmaybeprepared
with the exception of thickness, which is not required to be
in a laboratory or field setting, as the testing objectives dictate.
measured. Specimen thickness may however be measured as
The testing of the specimens is carried out according to the
partofthegeneralcharacterizationofthespecimen,andshould
provisionsofTestMethodD3039/D3039M.Theultimateforce
be reported if measured.
perunitwidthofthematerialisdeterminedfromthemaximum
NOTE 2—Calculations according to this method are based on force per
force carried before failure. If the load-strain response of the
unit coupon width and stiffness per unit coupon width. Specimen
material is monitored with strain gages or extensometers, then
thickness is not required for these calculations.
the stiffness of the material per unit width and the ultimate
8.2.1 Specimen Width—Minimum specimen width for uni-
tensile strain of the material may be determined.
directional shop-manufactured and wet lay-up FRP specimens
5. Significance and Use
shall be 25 mm [1.0 in.]. Minimum width for cross-ply
specimens shall be 25 mm [1.0 in.] for shop-manufactured
5.1 This test method can be used to obtain the tensile force
capacityandultimatetensilestrainofFRPmaterialusedforthe composites and 38 mm [1.5 in.] for wet lay-up composites.
strengthening of other structural materials such as, metals,
NOTE 3—For both unidirectional and cross-ply laminates, where fibers
timber, and reinforced concrete. The principal test variables
are used in large bundles (i.e, rovings, tows) that will be wider than 3 mm
could be the FRP constituents and fabrication method or the
[0.12 in.] when laid into the laminate, it is recommended that a specimen
size or type of FRP laminate. The obtained tensile properties width of 38 mm [1.5 in.] or higher be used.
D7565/D7565M–09
8.3 Specimen Preparation: many material systems. Edges should be flat and parallel
within the tolerances specified in 8.2. See Appendix X3 of
8.3.1 Wet Lay-up FRP—A polymer release film, typically
GuideD5687/D5687Mforspecificrecommendationsonspeci-
600 x 600 mm [24 x 24 in.] is placed on a smooth, flat
men machining methods.
horizontal surface. The release film should be at least 0.076
8.3.4 Labeling—Label the specimens so that they will be
mm [0.003 in.] thick and made of a polymer that will not
distinctfromeachotherandtraceablebacktotherawmaterial.
adhere to the resin used to impregnate the fibers. Usually,
Labeling must be unaffected by the test and must not affect the
acetate and nylon are acceptable. Resin is first applied to the
outcome of the test.
release film.The first ply of dry fiber preform with a minimum
dimensionof300x300mm[12x12in.]issaturatedorcoated
9. Calibration
with the specified amount of resin and placed on the release
film. This can be done using a properly calibrated saturator
9.1 The accuracy of all measuring equipment shall have
machineorusingamanufacturer-specifiedfibertoresinweight certified calibrations that are current at the time of use of the
ratio.Thespecifiednumberofpliesatthespecifiedangles(0or
equipment.
90 degrees) are sequentially impregnated with resin and
stacked onto the release film using the specified amount of 10. Conditioning
resinperplyperunitareaasintheactualinstallation.Usingthe
10.1 The recommended pre-test condition is effective mois-
flat edge of a small hand tool or a grooved roller, air bubbles
ture equilibrium at a specific relative humidity as established
are worked out of the material. The bubbles should be worked
byTestMethodD5229/D5229M;however,ifthetestrequestor
out in the direction of the primary fibers to ensure that no
doesnotexplicitlyspecifyapre-testconditioningenvironment,
damage is caused to the fibers. A second release film is then
noconditioningisrequiredandthespecimensmaybetestedas
placed over the material to provide protection. An alternative
prepared.
methodtoeliminateairbubblesistousetheflatedgeofasmall
10.2 The pre-test specimen conditioning process, to include
paddle on the outer side of the upper release film to force the
specifiedenvironmentalexposurelevelsandresultingmoisture
entrapped air out of the material with a screeding action in the
content, shall be reported with the test data.
primaryfiberdirection.Inordertoensureasmoothtopsurface
NOTE 6—The term moisture, as used in Test Method D5229/D5229M,
of the FRP material, a rigid flat plate should be placed on top
includes not only the vapor of a liquid and its condensate, but the liquid
of the top layer of release film while the resin cures. The
itself in large quantities, as for immersion.
laminate should be placed in an area of the jobsite so as to not
interfere with the installation and allowed to cure according to 11. Procedure
the manufacturer’s recommendation.After the specified curing
11.1 Follow procedures detailed in Test Method D3039/
procedure is complete, the release films are removed from the
D3039M Section 11 for testing the specimens. Record the
max
panel. Specimens may be cut and tabbed after the curing
maximum failure load P . If the stiffness of the specimen is
procedure.
to be calculated, record the load-strain relationship and the
strain at failure during the test.
NOTE 4—The final fiber, resin, and void content of the material will
depend on the method of rolling or screeding the material during
12. Calculation
fabrication.IftheaimoftestingistoevaluateFRPmaterialrepresentative
of the installed strengthening material, rolling and screeding procedures
12.1 Calculate the maximum tensile force per unit width
used to prepare specimens should resemble those used for the installed
and report results to three significant figures.
strengthening material.
max
NOTE 5—Guide D5687/D5687M provides guidelines for strictly con- P
F* 5 (1)
trolling the preparation of composite test specimens in the laboratory. w
Preparationofwetlay-upFRPshouldfollowtheseguidelinestotheextent
where:
thattheyarecompatiblewiththeintendedcureandlaminateconsolidati
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.