ASTM D2719-19

Standard Test Methods for Wood Structural Panels in Shear Through-the-Thickness

SIGNIFICANCE AND USE
3.1 The strength and modulus of rigidity of wood structural panels in shear through-the-thickness obtained by these test methods are required for the rigorous design of many lumber-panel structural components such as trusses with panel gussets, box beams, folded plate roofs, and space plane structures, as well as floor and roof diaphragms, and shear walls. These properties are of secondary importance in typical roof deck and sheathing applications, and in crates and shipping containers.  
3.2 Veneer produced by slicing or rotary peeling may contain fine checks or separations parallel to the grain on the knife side of the veneer that are produced as the knife is forced through the wood. These checks are termed “knife checks” to distinguish them from occasional checks that may be formed on the opposite side of the veneer by forces at the compression bar, and from checks caused by drying. Average depth of knife checks has been found to strongly influence shear properties in plywood panels and may be of significance in veneer incorporated in composite panels. Measurement of depth of knife checks is recommended in these test methods.  
3.3 To control or define other variables influencing shear properties, these test methods require determination of moisture content and elapsed time to failure. The conditioning of test material in controlled atmosphere and determination of specific gravity are recommended.
SCOPE
1.1 These test methods determine the shear through-the-thickness properties of wood structural panels associated with shear distortion of the major axis. Wood structural panels in use include plywood, oriented strand board, and composites of veneer and of wood-based layers. Three test methods are included which differ somewhat in their application:    
Test Method  
Section  
A. Small Panel Shear Test  
5  
B. Large Panel Shear Test  
6  
C. Two-Rail Shear Test  
7
The choice of test method will be determined in part by the purpose of the tests, characteristics of test material, and equipment availability. In general, Test Method B or C for large specimens is preferred when equipment, amount of test material, and experimental plan permit.  
1.1.1 Test Method A: Small Panel Shear Test—This test method is suitable for testing small samples of uniform material including investigations of the effects of grain direction or orientation and of many raw materials and manufacturing process variables which influence shear properties uniformly throughout the specimen. The test method is unsuited for determining effects of grade and manufacturing features such as density variations, knots, and core gaps within the specimen.  
1.1.2 Test Method B: Large Panel Shear Test—This test method is regarded as giving the most accurate modulus of rigidity and is therefore recommended for elastic tests of materials to be used in stress analysis studies of test structures. This test method also yields excellent shear strength values for clear material. However, in spite of the large size of the specimen, failures generally occur only in narrow zones at the perimeter of the test area. This characteristic, a result of the heavy perimeter framing, causes this test method to be generally unsuited for determining grade and manufacturing effects such as density variations, core gaps, and knots that are not uniformly distributed throughout the panel. Generally, only in cases where effects of these factors under conditions of heavy perimeter framing are desired, should the test method be applied.  
1.1.3 Test Method C: Two-Rail Shear Test—This test method is applicable to a wide variety of materials and problems. The specimen fabrication and test procedures are somewhat simpler than in Test Methods A and B. The specimen is free to shear parallel to its 24-in. (610-mm) length dimension anywhere within the 8-in. (203-mm) width between rails. Thus, the test method is well suited for determining grade and...

General Information

• Status: Published
• Publication Date: 31-Mar-2019
• ICS: 79.060.10 - Plywood
• Technical Committee: D07 - Wood
• Drafting Committee: D07.03 - Panel Products

Relations

• Refers: ASTM D4442-20 - Standard Test Methods for Direct Moisture Content Measurement of Wood and Wood-Based Materials
• Effective Date: 01-Mar-2020
• Refers: ASTM D4442-16 - Standard Test Methods for Direct Moisture Content Measurement of Wood and Wood-Based Materials
• Effective Date: 15-Nov-2016
• Refers: ASTM D4442-15 - Standard Test Methods for Direct Moisture Content Measurement of Wood and Wood-Based Materials
• Effective Date: 01-Jun-2015
• Refers: ASTM D2395-14e1 - Standard Test Methods for Density and Specific Gravity (Relative Density) of Wood and Wood-Based Materials
• Effective Date: 01-May-2014
• Refers: ASTM D2395-14 - Standard Test Methods for Density and Specific Gravity (Relative Density) of Wood and Wood-Based Materials
• Effective Date: 01-May-2014
• Refers: ASTM D4442-07 - Standard Test Methods for Direct Moisture Content Measurement of Wood and Wood-Base Materials
• Effective Date: 15-Nov-2007
• Refers: ASTM D2395-07ae1 - Standard Test Methods for Specific Gravity of Wood and Wood-Based Materials
• Effective Date: 01-Jul-2007
• Refers: ASTM D2395-07a - Standard Test Methods for Specific Gravity of Wood and Wood-Based Materials
• Effective Date: 01-Jul-2007
• Refers: ASTM D2395-07 - Standard Test Methods for Specific Gravity of Wood and Wood-Based Materials
• Effective Date: 01-Apr-2007
• Refers: ASTM D1037-06a - Standard Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
• Effective Date: 15-Oct-2006
• Refers: ASTM D1037-06 - Standard Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
• Effective Date: 15-Oct-2006
• Refers: ASTM D2395-06 - Standard Test Methods for Specific Gravity of Wood and Wood-Based Materials
• Effective Date: 01-Oct-2006
• Refers: ASTM D2395-02 - Standard Test Methods for Specific Gravity of Wood and Wood-Based Materials
• Effective Date: 10-Apr-2002
• Refers: ASTM D1037-99 - Standard Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
• Effective Date: 10-Apr-1999
• Refers: ASTM D4442-92(1997)e1 - Standard Test Methods for Direct Moisture Content Measurement of Wood and Wood-Base Materials
• Effective Date: 10-Mar-1997

Overview

ASTM D2719-19: Standard Test Methods for Wood Structural Panels in Shear Through-the-Thickness establishes test methods for determining the shear properties of wood structural panels, specifically focusing on the shear through-the-thickness. These methods are essential for evaluating materials such as plywood, oriented strand board (OSB), and composite wood-based panels. The standard ensures that accurate shear strength and modulus of rigidity values can be obtained, which are critical for the design and performance assessment of various structural applications where wood panels are subjected to shear loads.

Key Topics

• Shear Through-the-Thickness Testing: The standard defines procedures to determine a panel’s ability to resist shear forces applied perpendicular to its surface.
• Test Methods: ASTM D2719-19 outlines three test approaches:
  • Small Panel Shear Test (Method A): Best for uniform, smaller material samples, suitable for assessing the effect of grain direction and manufacturing variables.
  • Large Panel Shear Test (Method B): Yields the most accurate modulus of rigidity, preferred for elastic properties testing in stress analysis.
  • Two-Rail Shear Test (Method C): Offers versatility for a wide variety of materials and is ideal for evaluating grade and localized manufacturing effects like core gaps and knots.
• Preparation and Conditioning: The standard mandates specific specimen preparation, moisture content control, elapsed time to failure measurement, and recommendations for conditioning in a controlled environment.
• Variables Affecting Results:
  • Moisture content and specific gravity of the sample are crucial variables.
  • Depth of knife checks in veneer layers, which can directly impact shear properties, should be measured and reported.
• Reporting Requirements: Detailed information on test material, method, results, and any adjustment for stress distribution must be included in reports.

Applications

ASTM D2719-19 is fundamental for engineers, manufacturers, and quality control professionals involved in wood construction and material testing. The standard’s test methods are applied in:

• Structural Components Design: Used for the rigorous design of trusses with panel gussets, box beams, folded plate roofs, space frame structures, and other elements where panel shear strength and rigidity are primary concerns.
• Building Systems: Floor and roof diaphragms, shear walls, and other assemblies that rely on the accurate characterization of shear through-the-thickness properties.
• Panel Manufacturing: Product development and quality assurance in plywood, OSB, and veneer panel production.
• Research and Selection: Comparative evaluation of different wood structural panels and assessment of the impact of manufacturing variables.

While the properties measured are vital for specialized applications, they are of secondary importance in conventional uses such as typical roofing or sheathing, and in non-structural products like crates and shipping containers.

Related Standards

ASTM D2719-19 references several important standards to ensure consistency and accuracy, including:

• ASTM D1037 – Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
• ASTM D2395 – Test Methods for Density and Specific Gravity of Wood and Wood-Based Materials
• ASTM D4442 – Test Methods for Direct Moisture Content Measurement of Wood and Wood-Based Materials

These related standards provide methodologies for evaluating density, moisture content, and other properties that impact shear performance, supporting comprehensive material assessment and standardized reporting in the wood products industry.

Keywords

wood structural panels, shear test, shear through-the-thickness, plywood, oriented strand board, modulus of rigidity, ASTM D2719, wood panel testing, building materials standards

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: D2719 − 19
Standard Test Methods for
Wood Structural Panels in Shear Through-the-Thickness
This standard is issued under the fixed designation D2719; 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 uniformly distributed throughout the panel. Generally, only in
cases where effects of these factors under conditions of heavy
1.1 These test methods determine the shear through-the-
perimeter framing are desired, should the test method be
thickness properties of wood structural panels associated with
applied.
sheardistortionofthemajoraxis.Woodstructuralpanelsinuse
1.1.3 Test Method C: Two-Rail Shear Test—This test
include plywood, oriented strand board, and composites of
method is applicable to a wide variety of materials and
veneer and of wood-based layers. Three test methods are
problems. The specimen fabrication and test procedures are
included which differ somewhat in their application:
somewhatsimplerthaninTestMethodsAandB.Thespecimen
Test Method Section
isfreetoshearparalleltoits24-in.(610-mm)lengthdimension
A. Small Panel Shear Test 5
B. Large Panel Shear Test 6
anywherewithinthe8-in.(203-mm)widthbetweenrails.Thus,
C. Two-Rail Shear Test 7
the test method is well suited for determining grade and
The choice of test method will be determined in part by the
manufacturing effects such as core gaps and knots occupying
purpose of the tests, characteristics of test material, and
and affecting small areas. The test method is not so ideally
equipmentavailability.Ingeneral,TestMethodBorCforlarge
suited for determination of modulus of rigidity, but when
specimens is preferred when equipment, amount of test
adjusted for strain distribution effects, values approximating
material, and experimental plan permit.
those obtained by Test Method B result. The test method
1.1.1 Test Method A: Small Panel Shear Test—This test
simulates effects of heavy framing when expected planes of
method is suitable for testing small samples of uniform
weakness are oriented perpendicular to rails and no framing at
material including investigations of the effects of grain direc-
all when parallel to rails.
tion or orientation and of many raw materials and manufactur-
NOTE1—Asmallerscaleversionbasedontheprinciplesofthistwo-rail
ing process variables which influence shear properties uni-
shear method is contained in Test Methods D1037 Section 27. The results
formly throughout the specimen. The test method is unsuited
from Test Methods D1037 Section 27 may not be equivalent to the results
for determining effects of grade and manufacturing features
from Test Methods D2719 Method C.
such as density variations, knots, and core gaps within the
1.2 Significant differences, moderate to small in magnitude,
specimen.
among the three test methods have been found to exist when
1.1.2 Test Method B: Large Panel Shear Test—This test
these test methods are applied to plywood of clear straight-
method is regarded as giving the most accurate modulus of
grained veneers. Therefore, when comparisons are made
rigidity and is therefore recommended for elastic tests of
among test results, it is recommended that the same test
materials to be used in stress analysis studies of test structures.
method be used throughout.
This test method also yields excellent shear strength values for
clear material. However, in spite of the large size of the
1.3 This standard does not purport to address all of the
specimen, failures generally occur only in narrow zones at the
safety concerns, if any, associated with its use. It is the
perimeter of the test area. This characteristic, a result of the
responsibility of the user of this standard to establish appro-
heavy perimeter framing, causes this test method to be gener-
priate safety, health, and environmental practices and deter-
ally unsuited for determining grade and manufacturing effects
mine the applicability of regulatory limitations prior to use.
such as density variations, core gaps, and knots that are not
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard-
These test methods are under the jurisdiction of ASTM Committee D07 on
ization established in the Decision on Principles for the
Wood and are the direct responsibility of Subcommittee D07.03 on Panel Products.
Development of International Standards, Guides and Recom-
Current edition approved April 1, 2019. Published June 2019. Originally
mendations issued by the World Trade Organization Technical
approved in 1969. Last previous edition approved in 2013 as D2719 – 13. DOI:
10.1520/D2719-19. Barriers to Trade (TBT) Committee.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D2719 − 19
2. Referenced Documents glued-on blocks through a roller bracket assembly which
2 causes the resultant forces to act collinearly with the edge of
2.1 ASTM Standards:
the shear test area. This loading method most nearly produces
D1037 Test Methods for Evaluating Properties of Wood-
uniform pure shear. Shear strength is determined from maxi-
Base Fiber and Particle Panel Materials
mum load, and modulus of rigidity may be calculated from
D2395 TestMethodsforDensityandSpecificGravity(Rela-
measurements of compression strain along the compression
tive Density) of Wood and Wood-Based Materials
diagonal of the specimen.
D4442 Test Methods for Direct Moisture Content Measure-
ment of Wood and Wood-Based Materials 5.2 Test Specimen—Dimensions shown in Fig. 1 of the
panel specimen and reinforcing blocks depend upon panel
3. Significance and Use
thickness. Distance between blocks, L, shall not exceed 20
times specimen thickness, and block width and thickness shall
3.1 The strength and modulus of rigidity of wood structural
not be less than 5 and 2.5 times specimen thickness, respec-
panels in shear through-the-thickness obtained by these test
tively. Reinforcing blocks shall be of birch, maple, or other
methods are required for the rigorous design of many lumber-
wood of similar strength and rigidity. The average of specimen
panel structural components such as trusses with panel gussets,
thickness at two diagonally opposite corners and the dimen-
box beams, folded plate roofs, and space plane structures, as
sions of the shear area inside the reinforcing blocks shall be
well as floor and roof diaphragms, and shear walls. These
determined and recorded to the nearest 0.3 % or 0.001 in.
propertiesareofsecondaryimportanceintypicalroofdeckand
(0.025 mm), whichever is larger.
sheathing applications, and in crates and shipping containers.
5.3 Loading—Applytheloadbyspecialsteelloadingblocks
3.2 Veneer produced by slicing or rotary peeling may
which articulate with the rollers and pins attached to the test
contain fine checks or separations parallel to the grain on the
specimen. The angle between faces of the loading block shall
knife side of the veneer that are produced as the knife is forced
be 90° and between each face and the base the angle shall be
through the wood. These checks are termed “knife checks” to
45°. A spherical bearing block, preferably of the suspended,
distinguish them from occasional checks that may be formed
self-aligning type, shall be employed in the loading system.
on the opposite side of the veneer by forces at the compression
Apply the load continuously throughout the test with a uniform
bar, and from checks caused by drying.Average depth of knife
motion of the movable head of the testing machine equal to
checks has been found to strongly influence shear properties in
0.0025 in./in. of test area diagonal length/min (0.0025 mm/
plywood panels and may be of significance in veneer incorpo-
mm/min) corresponding to a shear strain rate of 0.005 in./in./
rated in composite panels. Measurement of depth of knife
min (0.005 mm/mm/min) within a permissible variation of
checks is recommended in these test methods.
625 %.
3.3 To control or define other variables influencing shear
5.3.1 Load each of the eight reinforcing blocks through
properties, these test methods require determination of mois-
roller brackets clamped to the reinforcing block across its
ture content and elapsed time to failure. The conditioning of
width or attached by other means and applying a compressive
test material in controlled atmosphere and determination of
force to the end of the reinforcing block through a surface
specific gravity are recommended.
2 2
contact area of at least 0.75 in. (484 mm ). These bearing
surfaces shall be firmly seated against the ends of their
4. Control of Moisture Content
respective reinforcing blocks during assembly. Rollers shall be
4.1 Wood structural panel samples to be tested at a specific
centered at the inner edge of the reinforcing block and 1.25 in.
temperature/relative humidity shall be conditioned to approxi-
(31.8 mm) from the loaded end of the reinforcing block.
mate constant weight in controlled atmospheric conditions
Moderate clamping pressure holding brackets to the reinforc-
beforegluingwoodrails.Conditioningoffabricatedspecimens
ing blocks applied perpendicular to the plane of the panel is
at the same temperature and relative humidity shall be contin-
permitted but shall not be excessive.
ued until the adhesive has cured sufficiently to ensure adequate
bond strength. For approximating moisture conditions of wood
structural panels used under dry conditions, a relative humidity
of 65 6 2 % at a temperature of 68 6 6 °F (20 6 3 °C) is
recommended.
5. Test Method A—Small Panel Shear Test
5.1 Summary—A specimen having a square shear area
bounded on each side by solid wood blocks glued to both sides
ofthespecimenisloadedincompressionalongonediagonalin
a conventional testing machine. Forces are applied to the
Metric Equivalents
1 1
For referenced ASTM standards, visit the ASTM website, www.astm.org, or in. ⁄16 ⁄2
mm 1.6 12.7
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. FIG. 1 Small Panel Shear Specimen and Dimensions
D2719 − 19
5.3.1.1 Fig. 2 illustrates detail of suitable roller brackets and 5.5 Calculation:
their method of attachment to the reinforcing blocks with small 5.5.1 Calculate the maximum shear stress or shear stress at
wood wedges. Fig. 3 shows a specimen loaded by means of the proportional limit as follows:
roller brackets, and Fig. 4 gives working drawings for these
T 5 0.707 P/Lt (1)
~ !
brackets. Brackets are clamped across the width of the rein-
where:
forcing blocks by driving small wedges between a projection
on the bracket and the reinforcing block. The clamping bolt is T = shear stress, psi (N/m ),
P = load (force), lbf (N),
used to apply moderate clamping pressure perpendicular to the
L = length of side of shear area, in. (m), (Fig. 1), and
planeofthespecimen.Otherbracketdevicesconformingtothe
t = thickness of shear specimen, in. (m).
requirements of 5.3.1 are permitted but shall be described in
detail in the report of test results.
5.5.2 Calculate modulus of rigidity from deformation data
5.3.1.2 Measure the elapsed time from initiation of loading
as follows:
to the maximum load and record to the nearest ⁄2 min.
G 5 0.3536 ~P/∆!@L / ~L·t!# (2)
5.4 Measurement of Deformation—When deformation data
where:
are desired for calculation of elastic properties, strain-
G = modulus of rigidity, psi (N/m ),
measuring devices having minimum gage length of 1 in. (25
P/∆ = slope of force/deformation curve, lbf/in. (N/m),
mm) shall be attached to both sides of the specimen and shall
L = gage length, in. (m), and
measure compression strain of the vertical (or compression)
t = thickness of shear specimen, in. (m).
diagonal, the gages being centered at its midpoint on each side.
A larger gage length is preferred but shall not exceed one half
6. Test Method B—Large Panel Shear Test
the length of the diagonal. Instruments and the accuracy of
their recording shall be to the nearest 0.0001 in. (0.0025 mm) 6.1 Summary—A specimen having a square shear area is
or 2 % of expected ultimate strain, whichever is smaller. Strain loaded through heavy lumber rails glued to both sides of the
readings of the two gages shall be averaged for computation of specimen at all four edges of the shear area. Loading by a
elastic properties. system of pins and yokes applies forces to the rails having a
FIG. 2 Small Panel Shear Specimen with Roller Brackets
D2719 − 19
FIG. 3 Small Panel Shear Specimen with Loading and Strain-Measuring Apparatus Placed in Testing Machine
resultant acting at the inside edge of the shear area. Maximum specimen. Use of a jig to position rails accurately at the time of
shear strength is determined from maximum load and modulus assembly or a light saw cut across the end of both rails after
of rigidity from elongation of the tension diagonal and corre- assembly may be helpful. Depending upon the method of
sponding loads. deformation measurement, holes for gage pins may be needed
as illustrated in Fig. 5. Average specimen thickness shall be
6.2 Test Specimens—Fig. 5 gives detail of the specimen as
determinedfrommeasurementsateachcornerofthesheararea
well as a suitable loading method. Shear area of the specimen
toanaccuracyof0.001in.(0.025mm).Widthandlengthofthe
shall not be less than 24 in. (610 mm) on a side, and shall not
shear area shall be measured to an accuracy of 0.01 in. (0.25
exceed 48 times total specimen thickness. When wood struc-
mm).
1 1
tural panels less than ⁄2 in. (12.7 mm) thick or less than ⁄48 the
side of the shear area are to be tested for shear strength, two or 6.3 Loading—Load the specimen loading jig assembly in
more thicknesses of wood structural panels may be glued tension. The resultant of forces applied to a pair of rails shall
together (major axis parallel) to form a test panel of the be a single force acting at, and parallel to, the edge of the shear
required thickness. Specimens to be tested for modulus of area. If the ends of rails are compression loaded, the jigs shall
rigidity only may be of lesser thickness provided sufficient data restrain any tendency for the rails to deflect laterally from the
can be obtained before the test is halted due to initiation of plane of the specimen. Fig. 6 shows the loading forces, their
buckling. Lumber rails having a length equal to the side of the resultants, and their components. Any lateral forces applied to
shear area, thickness not less than ⁄25 and width not less than the rails parallel to the plane of the specimen or any lateral
⁄6 the length of one side of the shear area shall be glued to the component parallel to the plane of the specimen of a force
wood structural panels with a rigid adhesive. Wider rails may applied t
...

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: D2719 − 13 D2719 − 19
Standard Test Methods for
Wood Structural Panels in Shear Through-the-Thickness
This standard is issued under the fixed designation D2719; 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 determine the shear through-the-thickness properties of wood structural panels associated with shear
distortion of the major axis. Structural Wood structural panels in use include plywood, oriented strand board, and composites of
veneer and of wood based wood-based layers. Three test methods are included which differ somewhat in their application:
Test Method Section
A. Small Panel Shear Test 5
B. Large Panel Shear Test 6
C. Two Rail Shear Test 7
C. Two-Rail Shear Test 7
The choice of test method will be determined in part by the purpose of the tests, characteristics of test material, and equipment
availability. In general, Test Method B or C for large specimens is preferred when equipment, amount of test material, and
experimental plan permit.
1.1.1 Test Method A: Small Panel Shear Test—This test method is suitable for testing small samples of uniform material
including investigations of the effects of grain direction or orientation and of many raw materials and manufacturing process
variables which influence shear properties uniformly throughout the specimen. The test method is unsuited for determining effects
of grade and manufacturing features such as density variations, knots, and core gaps within the specimen.
1.1.2 Test Method B: Large Panel Shear Test—This test method is regarded as giving the most accurate modulus of rigidity and
is therefore recommended for elastic tests of materials to be used in stress analysis studies of test structures. This test method also
yields excellent shear strength values for clear material. However, in spite of the large size of the specimen, failures generally occur
only in narrow zones at the perimeter of the test area. This characteristic, a result of the heavy perimeter framing, causes this test
method to be generally unsuited for determining grade and manufacturing effects such as density variations, core gaps, and knots
that are not uniformly distributed throughout the panel. Generally, only in cases where effects of these factors under conditions of
heavy perimeter framing are desired, should the test method be applied.
1.1.3 Test Method C: Two-Rail Shear Test—This test method is applicable to a wide variety of materials and problems. The
specimen fabrication and test procedures are somewhat simpler than in Test Methods A and B. The specimen is free to shear
parallel to its 24-in.(610-mm) 24-in. (610-mm) length dimension anywhere within the 8-in. (203-mm) width between rails. Thus,
the test method is well suited for determining grade and manufacturing effects such as core gaps and knots occupying and affecting
small areas. The test method is not so ideally suited for determination of modulus of rigidity, but when adjusted for strain
distribution effects, values approximating those obtained by Test Method B result. The test method simulates effects of heavy
framing when expected planes of weakness are oriented perpendicular to rails and no framing at all when parallel to rails.
NOTE 1—A smaller scale version based on the principles of this two rail two-rail shear method is contained in Test Methods D1037 sectionSection 27.
The results from Test Methods D1037 sectionSection 27 may not be equivalent to the results from Test Methods D2719 Method C.
1.2 Significant differences, moderate to small in magnitude, among the three test methods have been found to exist when these
test methods are applied to plywood of clear straight-grained veneers. Therefore, when comparisons are made among test results,
it is recommended that the same test method be used throughout.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.4 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.
These test methods are under the jurisdiction of ASTM Committee D07 on Wood and are the direct responsibility of Subcommittee D07.03 on Panel Products.
Current edition approved Oct. 1, 2013April 1, 2019. Published October 2013June 2019. Originally approved in 1969. Last previous edition approved in 20072013 as
D2719 – 89 (2007).D2719 – 13. DOI: 10.1520/D2719-13.10.1520/D2719-19.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D2719 − 19
2. Referenced Documents
2.1 ASTM Standards:
D1037 Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials
D2395 Test Methods for Density and Specific Gravity (Relative Density) of Wood and Wood-Based Materials
D4442 Test Methods for Direct Moisture Content Measurement of Wood and Wood-Based Materials
3. Significance and Use
3.1 The strength and modulus of rigidity of wood structural panels in shear through-the-thickness obtained by these test methods
are required for the rigorous design of many lumber-panel structural components such as trusses with panel gussets, box beams,
folded plate roofs, and space plane structures, as well as floor and roof diaphragms, and shear walls. These properties are of
secondary importance in typical roof deck and sheathing applications, and in crates and shipping containers.
3.2 Veneer produced by slicing or rotary peeling may contain fine checks or separations parallel to the grain on the knife side
of the veneer that are produced as the knife is forced through the wood. These checks are termed “knife checks” to distinguish
them from occasional checks that may be formed on the opposite side of the veneer by forces at the compression bar, and from
checks caused by drying. Average depth of knife checks has been found to strongly influence shear properties in plywood panels
and may be of significance in veneer incorporated in composite panels. Measurement of depth of knife checks is recommended
in these test methods.
3.3 To control or define other variables influencing shear properties, these test methods require determination of moisture
content and elapsed time to failure. The conditioning of test material in controlled atmosphere and determination of specific gravity
are recommended.
4. Control of Moisture Content
4.1 Structural Wood structural panel samples to be tested at a specific temperature/relative humidity shall be conditioned to
approximate constant weight in controlled atmospheric conditions before gluing wood rails. Conditioning of fabricated specimens
at the same temperature and relative humidity shall be continued until the adhesive has cured sufficiently to ensure adequate bond
strength. For approximating moisture conditions of wood structural panels used under dry conditions, a relative humidity of 65 6
2 % at a temperature of 68 6 6°F6 °F (20 6 3°C)3 °C) is recommended.
5. Test Method A—Small Panel Shear Test
5.1 Summary—A specimen having a square shear area bounded on each side by solid wood blocks glued to both sides of the
specimen is loaded in compression along one diagonal in a conventional testing machine. Forces are applied to the glued-on blocks
through a roller bracket assembly which causes the resultant forces to act collinearly with the edge of the shear test area. This
loading method most nearly produces uniform pure shear. Shear strength is determined from maximum load, and modulus of
rigidity may be calculated from measurements of compression strain along the compression diagonal of the specimen.
5.2 Test Specimen—Dimensions shown in Fig. 1 of the panel specimen and reinforcing blocks depend upon panel thickness.
Distance between blocks, L, shall not exceed 20 times specimen thickness, and block width and thickness shall not be less than
5 and 2.5 times specimen thickness, respectively. Reinforcing blocks shall be of birch, maple, or other wood of similar strength
Metric Equivalents
1 1
in. ⁄16 ⁄2
mm 1.6 12.7
FIG. 1 Small Panel Shear Specimen and Dimensions
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
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and rigidity. The average of specimen thickness at two diagonally opposite corners and the dimensions of the shear area inside the
reinforcing blocks shall be determined and recorded to the nearest 0.3 % or 0.001 in. (0.025 mm), whichever is larger.
5.3 Loading—Apply the load by special steel loading blocks which articulate with the rollers and pins attached to the test
specimen. The angle between faces of the loading block shall be 90° and between each face and the base the angle shall be 45°.
A spherical bearing block, preferably of the suspended, self-aligning type, shall be employed in the loading system. Apply the load
continuously throughout the test with a uniform motion of the movable head of the testing machine equal to 0.0025 in./in. of test
area diagonal length/min (0.0025 mm/mm/min) corresponding to a shear strain rate of 0.005 in./in./min (0.005 mm/mm/min)
within a permissible variation of 625 %.
5.3.1 Load each of the eight reinforcing blocks through roller brackets clamped to the reinforcing block across its width or
attached by other means and applying a compressive force to the end of the reinforcing block through a surface contact area of
2 2
at least 0.75 in. (484 mm ). These bearing surfaces shall be firmly seated against the ends of their respective reinforcing blocks
during assembly. Rollers shall be centered at the inner edge of the reinforcing block and 1.25 in. (31.8 mm) from the loaded end
of the reinforcing block. Moderate clamping pressure holding brackets to the reinforcing blocks applied perpendicular to the plane
of the panel is permitted but shall not be excessive.
5.3.1.1 Fig. 2 illustrates detail of suitable roller brackets and their method of attachment to the reinforcing blocks with small
wood wedges. Fig. 3 shows a specimen loaded by means of roller brackets, and Fig. 4 gives working drawings for these brackets.
Brackets are clamped across the width of the reinforcing blocks by driving small wedges between a projection on the bracket and
the reinforcing block. The clamping bolt is used to apply moderate clamping pressure perpendicular to the plane of the specimen.
Other bracket devices conforming to the requirements of 5.3.1 are permitted but shall be described in detail in the report of test
results.
5.3.1.2 Measure the elapsed time from initiation of loading to the maximum load and record to the nearest ⁄2 min.
5.4 Measurement of Deformation—When deformation data are desired for calculation of elastic properties, strain-measuring
devices having minimum gage length of 1 in. (25 mm) shall be attached to both sides of the specimen and shall measure
compression strain of the vertical (or compression) diagonal, the gages being centered at its midpoint on each side. A larger gage
FIG. 2 Small Panel Shear Specimen with Roller Brackets
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FIG. 3 Small Panel Shear Specimen with Loading and Strain-Measuring Apparatus Placed in Testing Machine
length is preferred but shall not exceed one half the length of the diagonal. Instruments and the accuracy of their recording shall
be to the nearest 0.0001 in. (0.0025 mm) or 2 % of expected ultimate strain, whichever is smaller. Strain readings of the two gages
shall be averaged for computation of elastic properties.
5.5 Calculation:
5.5.1 Calculate the maximum shear stress or shear stress at the proportional limit as follows:
T 5 0.707 ~P/Lt! (1)
where:
T = shear stress, psi (N/m ),
P = load (force), lbf (N),
L = length of side of shear area, in. (m), (Fig. 1), and
t = thickness of shear specimen, in. (m).
5.5.2 Calculate modulus of rigidity from deformation data as follows:
G 5 0.3536 P/Δ L / L·t # (2)
~ !@ ~ !
where:
G = modulus of rigidity, psi (N/m ),
P/Δ = slope of force/deformation curve, lbf/in. (N/m),
L = gage length, in. (m), and
t = thickness of shear specimen, in. (m).
6. Test Method B—Large Panel Shear Test
6.1 Summary—A specimen having a square shear area is loaded through heavy lumber rails glued to both sides of the specimen
at all four edges of the shear area. Loading by a system of pins and yokes applies forces to the rails having a resultant acting at
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NOTE 1—One inch equals 25.4 mm.
FIG. 4 Working Drawings for Small Panel Shear Test Loading Apparatus
the inside edge of the shear area. Maximum shear strength is determined from maximum load and modulus of rigidity from
elongation of the tension diagonal and corresponding loads.
6.2 Test Specimens—Fig. 5 gives detail of the specimen as well as a suitable loading method. Shear area of the specimen shall
not be less than 24 in. (610 mm) on a side, and shall not exceed 48 times total specimen thickness. When wood structural panels
1 1
less than ⁄2 in. (12.7 mm) thick or less than ⁄48 the side of the shear area isare to be tested for shear strength, two or more
thicknesses of wood structural panels may be glued together (major axis parallel) to form a test panel of the required thickness.
Specimens to be tested for modulus of rigidity only may be of lesser thickness provided sufficient data can be obtained before the
test is halted due to initiation of buckling. Lumber rails having a length equal to the side of the shear area, thickness not less than
1 1
⁄25 and width not less than ⁄6 the length of one side of the shear area shall be glued to the wood structural panels with a rigid
adhesive. Wider rails may be necessary to prevent rolling shear failures between thick or high-strength panels and the rails. Corners
of the wood structural panels specimen shall be notched with the inside corner of the notch provided with a fillet of ⁄2-in.
(12.7-mm) radius as shown in Fig. 5. Ends of the rails to which loads are applied shall form a flat plane perpendicular to the plane
of the specimen. Use of a jig to position rails accurately at the time of assembly or a light saw cut across the end of both rails after
assembly may be helpful. Depending upon the method of deformation measurement, holes for gage pins may be needed as
illustrated in Fig. 5. Average specimen thickness shall be determined from measurements at each corner of the shear area to an
accuracy of 0.001 in. (0.025 mm). Width and length of the shear area
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