ASTM D3043-00(2006)
(Test Method)Standard Test Methods for Structural Panels in Flexure
Standard Test Methods for Structural Panels in Flexure
SIGNIFICANCE AND USE
These methods give the flexural properties, principally strength and stiffness, of structural panels. These properties are of primary importance in most structural uses of panels whether in construction for floors, wall sheathing, roof decking, concrete form, or various space plane structures; packaging and materials handling for containers, crates, or pallets; or structural components such as stress-skin panels.
To control or define other variables influencing flexure properties, moisture content and time to failure must be determined. Conditioning of test material at controlled atmospheres to control test moisture content and determination of specific gravity are recommended. Comparisons of results of plywood, veneer composites, and laminates with solid wood or other plywood constructions will be greatly assisted if the thickness of the individual plies is measured to permit computation of section properties.
SCOPE
1.1 These test methods determine the flexural properties of strips cut from structural panels or panels up to 4 by 8 ft in size. Structural panels in use include plywood, waferboard, oriented strand board, and composites of veneer and of wood-based layers. Four methods of tests are included: SectionsMethod A-Center-Point Flexure Test5Method B-Two-Point Flexure Test 6Method C-Pure Moment Test 7 Method D-Flexure Test for Quality Assurance8
The choice of method will be dictated by the purpose of the test, type of material, and equipment availability. All methods are applicable to material that is relative uniform in strength and stiffness properties. Only Method C should be used to test material suspected of having strength or stiffness variations within a panel caused by density variations, knots, knot-holes, areas of distorted grain, fungal attack, or wide growth variations. However, Method B may be used to evaluate certain features such as core gaps and veneer joints in plywood panels where effects are readily projected to full panels. Method C generally is preferred where size of test material permits. Moments applied to fail specimens tested by Method A, B or D in which large deflections occur can be considerably larger than nominal. An approximate correction can be made.
1.2 Method A, Center-Point Flexure TestThis method is applicable to material that is uniform with respect to elastic and strength properties. Total deflection, and modulus of elasticity computed from it, include a relatively constant component attributable to shear deformation. It is well suited to investigations of many variables that influence properties uniformly throughout the panel in controlled studies and to test small, defect-free control specimens cut from large panels containing defects tested by the large-specimen method.
1.3 Method B, Two-Point Flexure Test This method, like Method A, is suited to the investigation of factors that influence strength and elastic properties uniformly throughout the panel, in controlled studies, and to testing small, defect free control specimens cut from large specimens tested by Method C. However, it may be used to determine the effects of finger joints, veneer joints and gaps, and other features which can be placed entirely between the load points and whose effects can be projected readily to full panel width. Deflection and modulus of elasticity obtained from this method are related to flexural stress only and do not contain a shear component. Significant errors in modulus of rupture can occur when nominal moment is used (see ).
1.4 Method C, Pure Moment TestThis method is ideally suited for evaluating effects of knots, knot-holes, areas of sloping grain, and patches for their effect on standard full-size panels. It is equally well suited for testing uniform or clear material whenever specimen size is adequate. Measured deformation and elastic constants are free of shear deformation effects; and panels can be bent to large deflections without incurring erro...
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: D3043 – 00 (Reapproved 2006)
Standard Test Methods for
Structural Panels in Flexure
This standard is issued under the fixed designation D3043; 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 strength and elastic properties uniformly throughout the panel,
in controlled studies, and to testing small, defect free control
1.1 These test methods determine the flexural properties of
specimens cut from large specimens tested by Method C.
stripscutfromstructuralpanelsorpanelsupto4by8ftinsize.
However, it may be used to determine the effects of finger
Structural panels in use include plywood, waferboard, oriented
joints, veneer joints and gaps, and other features which can be
strand board, and composites of veneer and of wood-based
placed entirely between the load points and whose effects can
layers. Four methods of tests are included:
be projected readily to full panel width. Deflection and
Sections
modulus of elasticity obtained from this method are related to
Method A—Center-Point Flexure Test 5
flexural stress only and do not contain a shear component.
Method B—Two-Point Flexure Test 6
Significant errors in modulus of rupture can occur when
Method C—Pure Moment Test 7
nominal moment is used (see Appendix X1).
Method D—Flexure Test for Quality Assurance 8
1.4 Method C, Pure Moment Test—This method is ideally
The choice of method will be dictated by the purpose of the
suited for evaluating effects of knots, knot-holes, areas of
test, type of material, and equipment availability. All methods
sloping grain, and patches for their effect on standard full-size
are applicable to material that is relative uniform in strength
panels. It is equally well suited for testing uniform or clear
and stiffness properties. Only Method C should be used to test
material whenever specimen size is adequate. Measured defor-
material suspected of having strength or stiffness variations
mation and elastic constants are free of shear deformation
within a panel caused by density variations, knots, knot-holes,
effects; and panels can be bent to large deflections without
areas of distorted grain, fungal attack, or wide growth varia-
incurring errors from horizontal force components occurring in
tions. However, Method B may be used to evaluate certain
other methods. Specimen size and span above certain mini-
features such as core gaps and veneer joints in plywood panels
mums are quite flexible. It is preferred when equipment is
where effects are readily projected to full panels. Method C
available.
generally is preferred where size of test material permits.
1.5 Method D, Flexure Test for Quality Assurance—This
Moments applied to fail specimens tested by MethodA, B or D
method, like Method A, is well suited to the investigation of
in which large deflections occur can be considerably larger
factors that influence bending strength and stiffness properties.
than nominal. An approximate correction can be made.
Also like Method A, this method uses small specimens in a
1.2 Method A, Center-Point Flexure Test—This method is
center-point simple span test configuration.This method uses a
applicabletomaterialthatisuniformwithrespecttoelasticand
span to depth ratio, specimen width, test fixture and test speed
strength properties. Total deflection, and modulus of elasticity
that make the method well suited for quality assurance. The
computed from it, include a relatively constant component
method is frequently used for quality assurance testing of
attributable to shear deformation. It is well suited to investi-
oriented strand board.
gations of many variables that influence properties uniformly
1.6 All methods can be used to determine modulus of
throughout the panel in controlled studies and to test small,
elasticity with sufficient accuracy. Modulus of rupture deter-
defect-free control specimens cut from large panels containing
mined by Methods A, B or D is subject to errors up to and
defects tested by the large-specimen method.
sometimes exceeding 20 % depending upon span, loading, and
1.3 Method B, Two-Point Flexure Test—This method, like
deflection at failure unless moment is computed in the rigorous
MethodA,issuitedtotheinvestigationoffactorsthatinfluence
manner outlined in Appendix X1 or corrections are made in
other ways. These errors are not present in Method C.
These methods are under the jurisdiction of ASTM Committee D07 on Wood
1.7 When comparisons are desired between results of speci-
and are the direct responsibility of Subcommittee D07.03 on Panel Products.
men groups, it is good practice to use the same method of test
Current edition approved Oct. 1, 2006. Published October 2006. Originally
´1 for all specimens, thus eliminating possible differences relat-
approved in 1972. Last previous edition approved in 2000 as D3043 – 00 . DOI:
able to test method.
10.1520/D3043-00R06.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D3043 – 00 (2006)
1.8 This standard does not purport to address all of the depths less than ⁄4 in. (6 mm) and 2 in. (50 mm) for greater
safety concerns, if any, associated with its use. It is the depths (Note 1). When the principal direction of the face plies,
responsibility of the user of this standard to establish appro- laminations,strands,orwafersisparalleltothespan,thelength
priate safety and health practices and determine the applica- of the specimen (Note 2) shall be not less than 48 times the
bility of regulatory limitations prior to use. depth plus 2 in.; when the principal direction of the face plies,
laminations, strands, or wafers is perpendicular to the span, the
2. Referenced Documents
specimen length shall be not less than 24 times the depth plus
2.1 ASTM Standards:
2 in. (Note 3).
D2395 Test Methods for Specific Gravity of Wood and
NOTE 1—In certain specific instances, it may be necessary or desirable
Wood-Based Materials
to test specimens having a width greater than 1 or 2 in. (25 or 50 mm). To
D4442 Test Methods for Direct Moisture Content Measure-
eliminate plate action when wider specimens are tested, the specimen
ment of Wood and Wood-Base Materials
width shall not exceed one third of the span length and precaution shall be
D4761 Test Methods for Mechanical Properties of Lumber taken to ensure uniform bearing across the entire width of the specimen at
the load and reaction points.
and Wood-Base Structural Material
NOTE 2—In cutting specimens to meet the length requirement, it is not
3. Significance and Use
intended that the length be changed for small variations in thickness.
Rather, it is intended that the nominal thickness of the material under test
3.1 These methods give the flexural properties, principally
should be used for determining the specimen length.
strength and stiffness, of structural panels.These properties are
of primary importance in most structural uses of panels
5.2.1 Measurements—Measure specimen thickness at mid-
whether in construction for floors, wall sheathing, roof deck- span at two points near each edge and record the average.
ing, concrete form, or various space plane structures; packag-
Measure to the nearest 0.001 in. (0.02 mm) or 0.3 %. Measure
ing and materials handling for containers, crates, or pallets; or width at mid-span to the nearest 0.3 %.
structural components such as stress-skin panels.
5.2.1.1 When needed for interpretation of test results for
3.2 To control or define other variables influencing flexure
plywood, veneer composites, and laminates measure thickness
properties, moisture content and time to failure must be
of each layer to the nearest 0.001 in. (0.02 mm) at mid-span at
determined. Conditioning of test material at controlled atmo-
each edge and record the average.
spheres to control test moisture content and determination of
5.3 Span—The span shall be at least 48 times the nominal
specific gravity are recommended. Comparisons of results of
depth when the principal direction of the face plies, lamina-
plywood, veneer composites, and laminates with solid wood or
tions, strands, or wafers of the test specimen is parallel to the
other plywood constructions will be greatly assisted if the
spanandatleast24timesthenominaldepthwhentheprincipal
thickness of the individual plies is measured to permit compu-
direction of the face plies, laminations, strands, or wafers is
tation of section properties.
perpendicular to the span (Note 3).
4. Control of Moisture Content NOTE 3—Establishment of a span-depth ratio is required to allow an
accurate comparison of test values for materials of different thicknesses. It
4.1 Structural panel samples to be tested at a specific
should be noted that the span is based on the nominal thickness of the
moisture content or relative humidity shall be conditioned to
material and it is not intended that the spans be changed for small
approximate constant mass in controlled atmospheric condi-
variations in thickness.
tions before testing. For structural panels used under dry
5.4 End Supports—Reaction points shall be capable of
conditions, a relative humidity of 65 6 5 % at a temperature of
freely compensating for warp of the test specimen by turning
68 6 6°F (20 6 3°C) is recommended.
laterally in a plane perpendicular to the specimen length so as
to apply load uniformly across its width. Design of end
5. Method A—Center-Point Flexure Test
supports shall place the center of rotation near the neutral axis
5.1 Summary—A conventional compression testing ma-
of the specimen of average thickness. Construction is shown in
chine is used to apply and measure a load at mid-span of a
detail in Fig. 1. Bearing points shall be rounded where they
smallflexurespecimen;andtheresultingdeflectionatmidspan
contact the specimen.
is measured or recorded. The test proceeds at a constant rate of
5.4.1 Useofbearingplatesisgenerallyrecommendedandis
head motion until either sufficient deflection data in the elastic
required wherever significant local deformation may occur.
range have been gathered or until specimen failure occurs. The
5.4.2 Use of roller bearings or plates and rollers to preclude
specimen is supported on reaction bearings which permit the
friction forces between end support and specimen is recom-
specimen and bearing plate to roll freely over the reactions as
mended in addition to the requirement of lateral compensation.
the specimen deflects.
Construction of a suitable end support using small roller
5.2 Test Specimen—The test specimen shall be rectangular
bearings in conjunction with a plate which clips to the end of
incrosssection.Thedepthofthespecimenshallbeequaltothe
the specimen is illustrated in Fig. 2 and Fig. 3. The use of a
thickness of material, and the width shall be 1 in. (25 mm) for
large ball bearing to provide lateral compensation for warp is
also illustrated. This method is particularly recommended for
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
thin specimens and small loads.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
5.4.3 As the specimen deflects during test, loads no longer
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. act in the direction assumed in formulas for calculating
D3043 – 00 (2006)
Metric Equiva- Metric Equiva-
Inch-Pound (in.) Inch-Pound (in.)
lents, (mm) lents, (mm)
1 1
⁄16 1.5 1 ⁄4 32
1 1
⁄8 31 ⁄2 38
⁄16 52 50
1 1
⁄4 62 ⁄16 52
⁄8 10 3 76
13 1
⁄32 10.3 5 ⁄2 140
⁄2 12 6 152
⁄8 23 12 305
⁄16 24 24 610
FIG. 1 Apparatus for Static Bending Test Showing Details of
Laterally Adjustable Supports
properties. For a discussion of these errors, their effects, and permissible variation of6 25 %. Load shall be measured to an
methods for reducing them, refer to Appendix X1.
accuracy of 61 % of indicated value or 0.4 percent of full
5.5 Loading Block—A loading block having a radius of
scale, whichever is larger. Calculate the rate of motion of the
curvature of approximately one and one-half times the depth of
movable head as follows:
the test specimen for a chord length of not less than twice the
N 5 zL /6d (1)
depth of the specimen shall be used. In cases where excessive
local deformation may occur, suitable bearing plates shall be
where:
used. Radius of curvature of bearing plate or block shall not be
N = rate of motion of moving head, in./min (mm/min),
so large as to cause bridging as the specimen bends.
L = span, in. (mm),
5.6 Loading Procedure—Apply the load with a continuous
d = depth of beam, in. (mm), and
motion of the movable head throughout the test. The rate of z = unit rate of fiber strain, in./in.·min (mm/mm·min) of
load application shall be such that the maximum fiber strain outer fiber length = 0.0015.
rate is equal to 0.0015 in./in. (mm/mm) per min within a
D3043 – 00 (2006)
FIG. 2 Reaction Bearing for Small Flexure Test Specimens
5.6.1 Measure the elapsed time from initiation of loading to
EI 5 ~L /48!~P/D! (2)
maximum load and record to the nearest ⁄2 min.
where:
5.7 Measurement of Deflection—Take data for load-
EI = modulus of elasticity, psi (MPa) 3 moment of iner-
deflection curves to determine the modulus of elasticity,
4 4
tia, in. (or mm ),
proportional limit, work to proportional limit, work to maxi-
P/D = slope of load—deflection curve, lbf/in. (N/mm),
mum load, and total work. Take deflections by the methods
4 4
I = moment of inertia, in. (mm ), and
indicated in Fig. 4 or Fig. 5, and take readings to the nearest
L = span, in. (mm).
0.001 in. (0.02 mm). Choose increments of load so that not less
5.8.1.1 Moment of inertia used in the computations in 5.8.1
than 12 and preferably 15 or more readings of load and
maybecalculatedinseveraldifferentwaysdependinguponthe
deflection are taken to the proportional limit.
requirements of the investigation. It may be based on the entire
5.7.1 Deflections also may be measured with transducer-
cross section, may include only the moment of inertia of layers
type gages and plotted simultaneously against load. In this
parallel to span, or may include all layers weighted in accor-
case, record deflection to an accuracy of at least 1 ⁄2 %of
dance with modulus of elasticity in the direction of bending
deformation at proportional limit and the recorded trace below
stress. State clearly the method employed in the report.
the proportional limit shall be at least 2 ⁄2 in. (64 mm) long or
⁄4 of full sca
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.