ASTM D7989-21

Standard Practice for Demonstrating Equivalent In-Plane Lateral Seismic Performance to Wood-Frame Shear Walls Sheathed with Wood Structural Panels

SIGNIFICANCE AND USE
5.1 This practice documents cyclic performance benchmarks for shear walls constructed with wood structural panel (WSP) sheathing attached to dimension lumber framing using common or galvanized box nails as defined in 3.2.8.  
5.2 Procedures described in this practice provide a method to evaluate an alternative shear wall system’s SEPs to demonstrate equivalent in-plane lateral seismic performance to the reference shear wall system.  
5.3 The procedures described in this practice do not address all factors to be considered for recognition of an alternative shear wall system. Such factors, as described in 1.4, vary by the end-use application and shall be addressed outside the scope of this standard through an evaluation of the acceptability of the alternative shear wall system in accordance with requirements of building codes and standards, as applicable.
SCOPE
1.1 This practice establishes a method for alternative shear wall systems to compare seismic equivalency parameters (SEP) derived from cyclic in-plane racking tests to performance targets derived from tests of light-frame shear walls constructed with wood structural panel (WSP) sheathing attached to dimension lumber framing using nails.  
1.2 This practice considers only the performance of shear walls subject to cyclic lateral loading, parallel to the plane of the shear wall. Design of walls with openings and performance for other wall functions, such as out-of-plane bending, combined shear and uplift, and so forth are not considered.  
1.3 This practice is applicable only to shear walls where all vertical-load-supporting elements are intact at the end of the in-plane lateral load test and remain capable of supporting gravity loads. Wall assemblies whose vertical-load-supporting elements buckle or otherwise become incapable of supporting gravity loads during the lateral load test are outside the scope of this practice. In addition, for bearing wall systems, this practice assumes that the shear wall system under evaluation has documented design procedures to ensure that vertical-load-supporting elements have adequate resistance to the combined effect of compression loads caused by overturning and gravity loads.  
1.4 This practice does not address height limitations, detailing requirements, wall openings, derivation of design values for strength and stiffness, or other requirements and limitations that may be necessary for an alternative shear wall system. These requirements shall be provided elsewhere, such as by a suitable product standard for the alternative shear wall system.  
1.5 This practice assumes that the stiffness or deformation of the alternative shear wall system can be estimated, and that design loads within a structure will be distributed among seismically equivalent wall systems based on their relative stiffness.  
1.6 This practice is not intended to preclude other rational means of evaluating seismic performance.  
1.7 This practice assumes that the alternative shear wall system may be used alone or in combination with wood-frame shear walls sheathed with wood structural panels.  
1.8 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.9 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.10 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)...

General Information

• Status: Published
• Publication Date: 31-Oct-2021
• ICS: 79.060.01 - Wood-based panels in general
• ICS: 91.060.10 - Walls. Partitions. Facades
• Technical Committee: D07 - Wood
• Drafting Committee: D07.05 - Wood Assemblies

Relations

• Refers: ASTM E2126-19 - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 01-Aug-2019
• Refers: ASTM F1667-18 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Sep-2018
• Refers: ASTM E2126-11(2018) - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 01-Jul-2018
• Refers: ASTM F1667-17 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Mar-2017
• Refers: ASTM F1667-15 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Sep-2015
• Refers: ASTM F1667-13 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Dec-2013
• Refers: ASTM F1667-11ae1 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Nov-2011
• Refers: ASTM F1667-11a - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Nov-2011
• Refers: ASTM E2126-11 - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 01-May-2011
• Refers: ASTM F1667-11 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 01-Jan-2011
• Refers: ASTM F1667-10 - Standard Specification for Driven Fasteners: Nails, Spikes, and Staples
• Effective Date: 15-Oct-2010
• Refers: ASTM E2126-10 - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 01-Sep-2010
• Refers: ASTM E2126-09 - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 01-Apr-2009
• Refers: ASTM E2126-08 - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 15-May-2008
• Refers: ASTM E2126-07a - Standard Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting Systems for Buildings
• Effective Date: 01-Dec-2007

Overview

ASTM D7989-21 is a widely recognized standard practice developed by ASTM International for demonstrating equivalent in-plane lateral seismic performance between alternative shear wall systems and traditional wood-frame shear walls sheathed with wood structural panels (WSP). This document outlines the procedures and parameters for verifying that an alternative shear wall system can provide seismic resistance comparable to the established reference system, which uses wood structural panels attached to dimension lumber framing with specified nails. Meeting this standard is essential for structural engineers, manufacturers, and code officials focused on earthquake-resilient construction using light-frame buildings.

Key Topics

• Seismic Equivalency Parameters (SEP):
  The practice defines and benchmarks key seismic performance parameters, including:

  • Drift capacity
  • Component overstrength
  • Ductility
  • Maintenance of gravity-load support after cyclic loading

• Testing Requirements:
  Shear walls are subjected to cyclic in-plane racking tests (using ASTM E2126 methods), with performance targets established based on comprehensive reference data. Testing must be performed on wall assemblies representative of the intended application, focusing on:

  • Aspect ratio and wall height
  • Fastener types and spacing
  • Sheathing joints and framing details
  • Anchorage and overturning restraint

• Applicability and Limitations:
  The standard applies strictly to in-plane lateral performance. It does not consider:

  • Walls with openings (windows, doors)
  • Out-of-plane bending or combined shear and uplift performance
  • Design values and product-specific limitations, which should be addressed by additional relevant standards

• Recognition of Alternative Shear Wall Systems:
  ASTM D7989-21 provides a practical pathway for new or modified wall assemblies (e.g., with alternative sheathing, fasteners, or framing) to demonstrate seismic equivalence for building code approval.

Applications

ASTM D7989-21 is primarily applied in:

• Product Development and Evaluation:
  Manufacturers of innovative wall systems use this standard to document seismic performance equivalence, enabling market entry for new products or designs.

• Code Compliance:
  Engineers and code officials rely on this standard to assess whether alternative shear wall systems can be used in seismically active regions where wood structural panel shear walls are the baseline.

• Quality Assurance and Research:
  Researchers and quality assurance professionals utilize the defined procedures for benchmarking and comparing cyclic performance across a range of wall designs.

• Hybrid Construction:
  The standard supports the integration of alternative wall systems alongside traditional WSP-sheathed shear walls within the same structure, ensuring predictable earthquake performance and load sharing based on relative stiffness.

Related Standards

Several supporting standards and documents are referenced and commonly used in conjunction with ASTM D7989-21:

• ASTM E2126:
  Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of Lateral Force Resisting Systems for Buildings

• ASTM F1667:
  Specification for Driven Fasteners: Nails, Spikes, and Staples

• PS1 and PS2 (Department of Commerce):
  PS1 - Structural Plywood
  PS2 - Performance Standard for Wood-Based Structural-Use Panels

These standards ensure that the materials, test methods, and performance criteria used are consistent and internationally recognized for structural wood construction.

Practical Value

By following ASTM D7989-21, stakeholders gain:

• Clear protocols to demonstrate earthquake resistance of alternative shear wall systems relative to established wood structural panel solutions.
• Facilitation of innovation in seismic wall construction while maintaining safety, code compliance, and structural reliability.
• Streamlined approval processes for new products, reducing the need for redundant benchmark testing and helping the industry adopt advancements more rapidly.

Keywords: ASTM D7989-21, seismic performance, shear wall, wood structural panel, in-plane lateral load, earthquake resistance, alternative wall systems, cyclic racking test, building code compliance, structural engineering.

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: D7989 − 21
Standard Practice for
Demonstrating Equivalent In-Plane Lateral Seismic
Performance to Wood-Frame Shear Walls Sheathed with
Wood Structural Panels
This standard is issued under the fixed designation D7989; 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 1.6 This practice is not intended to preclude other rational
means of evaluating seismic performance.
1.1 This practice establishes a method for alternative shear
wall systems to compare seismic equivalency parameters
1.7 This practice assumes that the alternative shear wall
(SEP) derived from cyclic in-plane racking tests to perfor- system may be used alone or in combination with wood-frame
mance targets derived from tests of light-frame shear walls
shear walls sheathed with wood structural panels.
constructed with wood structural panel (WSP) sheathing at-
1.8 Units—The values stated in inch-pound units are to be
tached to dimension lumber framing using nails.
regarded as standard. The values given in parentheses are
1.2 This practice considers only the performance of shear
mathematical conversions to SI units that are provided for
walls subject to cyclic lateral loading, parallel to the plane of
information only and are not considered standard.
the shear wall. Design of walls with openings and performance
1.9 This standard does not purport to address all of the
for other wall functions, such as out-of-plane bending, com-
safety concerns, if any, associated with its use. It is the
bined shear and uplift, and so forth are not considered.
responsibility of the user of this standard to establish appro-
1.3 This practice is applicable only to shear walls where all
priate safety, health, and environmental practices and deter-
vertical-load-supporting elements are intact at the end of the
mine the applicability of regulatory limitations prior to use.
in-plane lateral load test and remain capable of supporting
1.10 This international standard was developed in accor-
gravity loads. Wall assemblies whose vertical-load-supporting
dance with internationally recognized principles on standard-
elements buckle or otherwise become incapable of supporting
ization established in the Decision on Principles for the
gravity loads during the lateral load test are outside the scope
Development of International Standards, Guides and Recom-
of this practice. In addition, for bearing wall systems, this
mendations issued by the World Trade Organization Technical
practice assumes that the shear wall system under evaluation
Barriers to Trade (TBT) Committee.
has documented design procedures to ensure that vertical-load-
supporting elements have adequate resistance to the combined 2. Referenced Documents
effect of compression loads caused by overturning and gravity
2.1 ASTM Standards:
loads.
E2126 Test Methods for Cyclic (Reversed) Load Test for
1.4 This practice does not address height limitations, detail-
Shear Resistance ofVertical Elements of the Lateral Force
ing requirements, wall openings, derivation of design values
Resisting Systems for Buildings
for strength and stiffness, or other requirements and limitations
F1667 Specification for Driven Fasteners: Nails, Spikes, and
that may be necessary for an alternative shear wall system.
Staples
These requirements shall be provided elsewhere, such as by a
2.2 Other Documents:
suitable product standard for the alternative shear wall system.
PS1 Structural Plywood, U.S. Department of Commerce
1.5 This practice assumes that the stiffness or deformation
Voluntary Product Standard
of the alternative shear wall system can be estimated, and that
PS2 Performance Standard for Wood-Based Structural Use
design loads within a structure will be distributed among
seismically equivalent wall systems based on their relative
stiffness.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
This practice is under the jurisdiction ofASTM Committee D07 on Wood and Standards volume information, refer to the standard’s Document Summary page on
is the direct responsibility of Subcommittee D07.05 on Wood Assemblies. the ASTM website.
Current edition approved Nov. 1, 2021. Published December 2021. Originally Online, Available: https://www.nist.gov/system/files/documents/2019/12/16/
approved in 2015. Last previous edition approved in 2020 as D7989 – 20. DOI: PS%201%2019%20final%20WERB-approved%20%28NIST%20vers%2011-18-
10.1520/D7989-21. 2019%29%2B.pdf
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7989 − 21
Panels, U.S. Department of Commerce Voluntary Product 3.2.12 wood structural panel (WSP)—panel manufactured
Standard in accordance with PS1 or PS2 from veneers; wood strands or
wafers;oracombinationofveneerandwoodstrandsorwafers;
3. Terminology
bonded together with waterproof resins or other suitable
bonding systems.
3.1 Definitions—The definitions in Test Methods E2126
also apply to this practice.
4. Summary of Practice
3.2 Definitions Specific to this Practice:
4.1 Shear walls are tested in accordance with Test Methods
3.2.1 aspect ratio, n—ratio of a shear wall’s height divided
E2126, and the average envelope curve is generated for each
by its length.
specimen as defined in 3.2.4 of Test Methods E2126.
3.2.2 allowable design load, n—maximum in-plane racking
4.2 SEPs are determined from the average envelope curve
resistance using an allowable stress design methodology as-
for each specimen, and the average SEPs for each tested shear
signed to a tested shear wall configuration for seismic design.
wall configuration are compared to the benchmark parameters.
3.2.3 alternative shear wall system, n—shear wall system
4.3 Seismic equivalency is established if each of the SEPs
for which seismic equivalence to the reference shear wall
for the alternative shear wall system meets specified require-
system is sought.
ments and the vertical-load-supporting elements are intact and
3.2.3.1 Discussion—The alternative shear wall system may
capable of supporting gravity loads.
represent a range of possibilities including pre-fabricated or
field-fabricated wall assemblies that do not resemble the
5. Significance and Use
reference shear wall system or assemblies with minor modifi-
5.1 This practice documents cyclic performance bench-
cations to the reference system, such as the use of alternative
marks for shear walls constructed with wood structural panel
fasteners, framing, or sheathing.
(WSP) sheathing attached to dimension lumber framing using
3.2.4 component overstrength, n—ratioofpeakloaddivided
common or galvanized box nails as defined in 3.2.8.
by allowable design load.
5.2 Procedures described in this practice provide a method
3.2.5 drift capacity, n—ultimate cyclic displacement on the
to evaluate an alternative shear wall system’s SEPs to demon-
average envelope curve defined in Test Methods E2126 corre-
strate equivalent in-plane lateral seismic performance to the
sponding to the failure limit state.
reference shear wall system.
3.2.6 ductility, n—ratio of drift capacity divided by the
5.3 The procedures described in this practice do not address
displacement on the average envelope curve defined in Test
all factors to be considered for recognition of an alternative
Methods E2126 corresponding to the allowable design load.
shearwallsystem.Suchfactors,asdescribedin1.4,varybythe
3.2.7 peak load, n—maximum load on the average envelope
end-use application and shall be addressed outside the scope of
curve defined in Test Methods E2126.
this standard through an evaluation of the acceptability of the
3.2.8 reference shear wall system, n—wood-frame shear
alternative shear wall system in accordance with requirements
wall system used for the equivalence benchmark, consisting of
of building codes and standards, as applicable.
wood structural panel sheathing attached to dimension lumber
framing using 6d, 8d, or 10d common (Specification F1667,
6. Testing Requirements
Table 14, Type 1, Style 9) or galvanized box (Specification
6.1 Test Program Design—The test program used to evalu-
F1667, Table 5, Type 1, Style 3A) nails, with full round heads,
ate the alternative shear wall system shall be based on
complying with F1667.
consideration of the range of intended applications and vari-
ables that have a potential impact on the seismic performance.
3.2.8.1 Discussion—TableX1.1providessummaryinforma-
Variables may include, but are not limited to, allowable design
tion for the walls evaluated to represent the reference shear
loads, configuration options, material variations, overturning
wall system.
restraint types, fastener spacings, and aspect ratios.
3.2.9 seismic equivalence parameters (SEP), n—keyparam-
eters representing seismic performance of shear walls, specifi-
6.2 Number of Tests—For each tested shear wall
cally drift capacity, component overstrength, ductility, and
configuration, the number of replicates shall be as required in
maintenance of vertical-load-supporting capability.
8.1 of Test Methods E2126 or as required by the applicable
3.2.10 shear wall, n—wall designed to resist lateral racking
product standard.
shear forces parallel to the plane of the wall.
6.3 Loading—Cyclic lateral load tests shall be conducted
3.2.11 shear wall configuration, n—shear wall of a specific
using Method C from Test Methods E2126.
heightandlengthrepresentingonepossiblecaseofashearwall
6.3.1 Load Beam—The load beam used to apply load to the
system and consisting of a specific arrangement of
test assembly shall comply with 7.3.1 of Test Methods E2126.
components,suchasframing,fasteners,sheathing,andanchor-
6.4 Rigid Base—Testing shall be conducted on a rigid base,
age.
such that the performance of the test specimens is not influ-
enced by deformation of the base structure. The specimens
shall be anchored directly to the base and shall be in full
Online, Available: https://www.nist.gov/system/files/documents/2019/05/09/ps
_2-18_final_apr_2019_dfa_reviewed.pdf contact with the base.
D7989 − 21
6.5 Test Specimen Construction—Specimens shall be con- 6.5.5 Sheathing Connections—Where sheathing attached to
structed using details consistent with the intended application. framing is used to resist lateral loads, the sheathing fasteners
Sheathing, if present, shall not bear on any portion of the test shall be installed using the minimum edge distance recom-
fixture or the loading beam during the tests, except where the mendedbythesheathingmanufactureralongallfoursheathing
specified end-use installation requires the sheathing to bear on edges. The number of fasteners installed along each edge shall
supporting elements, such as foundations or sill plates. If be equal to the length of the sheathing edge divided by the
bearingonawoodsillplateisspecifiedinapplication,asimilar specified fastener spacing, plus one. Spacing between the
wood sill plate shall be included in the tested assembly. sheathing corner fastener and the next adjacent fastener is
permitted to be less than the recommended spacing to accom-
6.5.1 Aspect Ratios—Aspect ratios and wall dimensions
modate the required edge distance. Sheathing fasteners placed
shall be consistent with the intended application.
in the field of the panel, if any, shall be positioned as required
6.5.1.1 Alternative shear wall systems that are similar to the
by the design. Sheathing fasteners shall be driven so that the
reference system (that is, repetitive vertical stud framing
head of the fastener contacts the surface of the sheathing, but
spaced at 24 in. on center or less with structural sheathing
not so deep as to crush the surface, unless specified differently
nailed to framing), except for variations in framing materials,
by the manufacturer.
sheathing materials, or fasteners, shall be evaluated using an
aspect ratio of 1:1 and a minimum wall height of 8 ft (2.4 m).
7. Evaluation of Cyclic Response
6.5.1.2 Alternative shear wall systems that vary more sig-
7.1 Average Envelope Curve—The average envelope curve
nificantly from the reference system described in 6.5.1.1 shall
shall be generated for each test specimen as defined in 3.2.4 of
be evaluated using the range of aspect ratios for the intended
Test Methods E2126.
application.
7.2 SEP Determination—The component overstrength, drift
6.5.2 Sheathing Joints—Alternative shear wall systems that
capacity, and ductility shall be determined for each specimen
will include discrete sheathing panels shall include at least one
as defined in 3.2. The average values calculated for all
vertical sheathing joint if such joints will occur in application.
replicates of a tested shear wall configuration shall be the SEPs
Test specimens may include horizontal sheathing joints as
for the alternative shear wall configuration. The results of
necessary,suchaswherespecimenheightsexceedpanelheight
multiple shear wall configurations shall not be averaged or
or where sheathing is intended to be installed with the long
otherwise combined for the evaluation.
dimension perpendicular to the longitudinal axis of the studs.
6.5.3 Framing—Where applicable, the stud and plate
7.3 Assessment of Vertical-Load-Supporting Elements—The
material, species, grade, size, and spacing shall be representa-
condition of the vertical-load-supporting elements shall be
tive of that used in application. Framing shall meet the
visually assessed to qualitatively determine whether the capa-
requirements of 6.3 in Test Methods E2126.
bility to support gravity loads is retained.
6.5.3.1 For alternative systems described in6.5.1.1, framing
NOTE 1—Visual assessment of vertical-load-supporting elements relies
with the smallest standard stud and plate cross sections
on examination during and after the test for observation of occurrence of
expected in application shall be used, and the smallest number
failure modes, such as buckling, that compromise the wall assembly’s
ability to carry vertical load. For wood-frame walls that comprise the
of end post studs that can practically be employed in accor-
reference shear wall system, the lack of observed buckling or other
dance with standard design provisions shall be used.
significant vertical load limiting failure modes for the studs and end posts
6.5.4 Anchorage and Framing Connections—Shear
has been used as visual confirmation of retained ability to support gravity
anchorage, overturning restraint, and framing connections,
loads.
including connections between individual plies of built-up
8. Requirements for Equivalency
posts, shall be representative of typical connections used in
8.1 Table 1 provides the SEP performance targets based on
application and shall be designed and detailed to optimize to
tests of the reference shear wall system conducted in accor-
the extent practical the design resistance of the connections to
dance with Method C of Test Methods E2126.
the design load of the shear wall.
6.5.4.1 Alternative systems described in 6.5.1.1 shall be
8.2 Seismic equivalency is established if the SEPs for the
tested with bolts for shear anchorage and eccentric-type hold
alternative shear wall system meet requirements specified in
downs positioned inside the wall for overturning restraint
Table 1 and if the vertical-load-supporting elements are judged
unless use of an alternative shear anchorage or hold down
to retain capability to support gravity loads.
system, or both, will be required in application. Where either
9. Keywords
an alternative shear anchorage or overturning restraint is
required in application, the specified alternative shall be 9.1 cyclic loads; earthquake, shear wall; lateral force; seis-
permitted for the evaluation. mic; wood structural panel;
D7989 − 21
TABLE 1 SEPs for Equivalency to Nailed, Wood-Frame, WSP Shear Walls
Parameter SEP Requirement
P
peak, avg
Component Overstrength
2.5# #5.0
P
ASD
Drift Capacity ∆ $0.028h
U, avg
∆
U, avg
Ductility
$11
∆
ASD, avg
P = average peak load for all replicates of the wall configuration,
peak, avg
P = allowable design load for the wall configuration,
ASD
∆ = average ultimate displacement for all replicates of the wall configuration,
U, avg
h = height of the shear wall, and
∆ = average displacement corresponding to the allowable design load for all replicates of the wall configuration.
ASD, avg
APPENDIX
(Nonmandatory Information)
X1. COMMENTARY
X1.1 Introduction X1.2 Development of Equivalency Procedure
X1.2.1 In 2007, an ICC Evaluation Service task group was
X1.1.1 Shear walls constructed with wood structural panels
formed to create an approach for a new structural system to
(WSP) fastened to sawn lumber framing with common or
demonstrate seismic equivalence to wood-frame WSP shear
galvanized box nails are widely used in construction. This
walls (1, 2). This task group included consulting engineers,
system serves as the reference shear wall construction for this
academics, trade association representatives, product
practice. When subjected to cyclic loads, this reference system
manufacturers, and wood industry professionals. The initial
demonstrates desirable ductile yield modes with significant
focusofthegroupwastoderiveaprocedurethatcouldbeused
drift capacity, ductility, and overstrength. The seismic design
to judge whether high-aspect-ratio, prefabricated shear panels
provisions for engineered light-frame wood construction in
could be assigned the seismic design coefficients and factors
North America account for this behavior by assigning appro-
associated with the WSP reference system.
priateseismicdesigncoefficients.Thesecoefficientsareusedto
determine the seismic design loads on a structure and to
X1.2.2 Several different quantitative parameters from cyclic
estimate the building response to an earthquake. shear wall testing were reviewed by the industry task group to
represent the seismic performance of the reference system (1,
X1.1.2 As new structural systems are developed or modifi-
2). Ultimately, they selected drift capacity, component
cations to the reference system are introduced, the seismic
overstrength, and ductility, as defined in this practice, to
response capabilities of the new or modified systems are often
represent seismic performance for the reference system.
questioned. For example, will the response of the alternative
X1.2.3 Inaddition,thetaskgroupobservedthatdegradation
system be significantly different from the benchmark system or
of the sheathing and fasteners under progressive cyclic lateral
will the use of a proprietary sheathing panel, fastener, or
loading does not typically compromise the ability of the wood
framingmaterialfundamentallychangetheseismicresponseof
studs in the reference system to support vertical loads.
the benchmark wall system? Can an entirely new wall system
Therefore, in the absence of a consensus standard to conduct
or product be intermixed with the benchmark system and
combined vertical and lateral load testing, it was determined
behave in a compatible fashion? This practice provides a
that alternative systems should also demonstrate this charac-
relatively simple, quantitative method for comparison of cyclic
teristic (1, 2). Examples of failure modes that could be induced
resistance parameters to establish seismic equivalence.
in a lateral load only test that would inhibit the ability to carry
However, there are many considerations beyond the results of
a simultaneous vertical load might include buckling, bending
the in-plane lateral tests performed in accordance with this
or compression fracture of a non-redundant assembly, or
practice for evaluation of SEPs that must be considered before
similar failure for multiple framing members within light-
anewsystemcanbedeemedequivalenttothereferencesystem
frame assembly. Given the wide variety of potential wall
for all aspects of building performance in a seismic event. For
assemblies that might be reviewed under this protocol, it is not
this reason, it is required for the alternative shear wall system
possible to prescriptively list acceptable and unacceptable
to have documentation, such as a product standard, that
failure modes and some practical engineering judgement and
addresses the specific issues listed in 1.4, as well as any other
rationalization is required for this qualitative assessment.
relevant issues necessary to the use of the product. Assessing
Alternativesystemsthatdemonstratesignificantdegradationof
all aspects of seismic performance for the end use application
the vertical-load-supporting elements during the lateral load
is beyond the scope of this standard. test or exhibit questionable failure modes cannot achieve
D7989 − 21
equivalence through this protocol alone and some form of CUREE protocol (Method C of Test Methods E2126). This
combined load testing should be considered. load protocol was chosen because it is commonly used by the
wood products industry in the United States, and because the
X1.2.4 It is an underlying assumption of this procedure that
failure modes observed with this loading protocol are consis-
an alternative shear wall system judged to be equivalent
tentwithfailuresobservedduetorealearthquakes.Becausethe
through this practice may either be used alone or in combina-
results of cyclic tests
...

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: D7989 − 20 D7989 − 21
Standard Practice for
Demonstrating Equivalent In-Plane Lateral Seismic
Performance to Wood-Frame Shear Walls Sheathed with
Wood Structural Panels
This standard is issued under the fixed designation D7989; 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 practice establishes a method for alternative shear wall systems to compare seismic equivalency parameters (SEP) derived
from cyclic in-plane racking tests to performance targets derived from tests of light-frame shear walls constructed with wood
structural panel (WSP) sheathing attached to dimension lumber framing using nails.
1.2 This practice considers only the performance of shear walls subject to cyclic lateral loading, parallel to the plane of the shear
wall. Design of walls with openings and performance for other wall functions, such as out-of-plane bending, combined shear and
uplift, and so forth are not considered.
1.3 This practice is applicable only to shear walls where all vertical-load-supporting elements are intact at the end of the in-plane
lateral load test and remain capable of supporting gravity loads. Wall assemblies whose vertical-load-supporting elements buckle
or otherwise become incapable of supporting gravity loads during the lateral load test are outside the scope of this practice. In
addition, for bearing wall systems, this practice assumes that the shear wall system under evaluation has documented design
procedures to ensure that vertical-load-supporting elements have adequate resistance to the combined effect of compression loads
caused by overturning and gravity loads.
1.4 This practice does not address height limitations, detailing requirements, wall openings, derivation of design values for
strength and stiffness, or other requirements and limitations that may be necessary for an alternative shear wall system. These
requirements shall be provided elsewhere, such as by a suitable product standard for the alternative shear wall system.
1.5 This practice assumes that the stiffness or deformation of the alternative shear wall system can be estimated, and that design
loads within a structure will be distributed among seismically equivalent wall systems based on their relative stiffness.
1.6 This practice is not intended to preclude other rational means of evaluating seismic performance.
1.7 This practice assumes that the alternative shear wall system may be used alone or in combination with wood-frame shear walls
sheathed with wood structural panels.
1.8 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
This test method practice is under the jurisdiction of ASTM Committee D07 on Wood and is the direct responsibility of Subcommittee D07.05 on Wood Assemblies.
Current edition approved Nov. 1, 2020Nov. 1, 2021. Published December 2020December 2021. Originally approved in 2015. Last previous edition approved in 20182020
as D7989 – 18.20. DOI: 10.1520/D7989-20.10.1520/D7989-21.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7989 − 21
1.9 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.
1.9 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.10 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
2.1 ASTM Standards:
E2126 Test Methods for Cyclic (Reversed) Load Test for Shear Resistance of Vertical Elements of the Lateral Force Resisting
Systems for Buildings
F1667 Specification for Driven Fasteners: Nails, Spikes, and Staples
2.2 Other Documents:
PS1 Structural Plywood, U.S. Department of Commerce Voluntary Product Standard
PS2 Performance Standard for Wood-Based Structural Use Panels, U.S. Department of Commerce Voluntary Product Standard
3. Terminology
3.1 Definitions—The definitions in Test Methods E2126 also apply to this practice.
3.2 Definitions Specific to this Practice:
3.2.1 aspect ratio, n—ratio of a shear wall’s height divided by its length.
3.2.2 allowable design load, n—maximum in-plane racking resistance using an allowable stress design methodology assigned to
a tested shear wall configuration for seismic design.
3.2.3 alternative shear wall system, n—shear wall system for which seismic equivalence to the reference shear wall system is
sought.
3.2.3.1 Discussion—
The alternative shear wall system may represent a range of possibilities including pre-fabricated or field-fabricated wall assemblies
that do not resemble the reference shear wall system or assemblies with minor modifications to the reference system, such as the
use of alternative fasteners, framing, or sheathing.
3.2.4 component overstrength, n—ratio of peak load divided by allowable design load.
3.2.5 drift capacity, n—ultimate cyclic displacement on the average envelope curve defined in Test Methods E2126 corresponding
to the failure limit state.
3.2.6 ductility, n—ratio of drift capacity divided by the displacement on the average envelope curve defined in Test Methods E2126
corresponding to the allowable design load.
3.2.7 peak load, n—maximum load on the average envelope curve defined in Test Methods E2126.
3.2.8 reference shear wall system, n—wood-frame shear wall system used for the equivalence benchmark, consisting of wood
structural panel sheathing attached to dimension lumber framing using 6d, 8d, or 10d common (Specification F1667, Table 14,
Type 1, Style 9) or galvanized box (Specification F1667, Table 5, Type 1, Style 3A) nails, with full round heads, complying with
F1667.
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.
Online, Available: https://www.nist.gov/system/files/documents/2019/12/16/PS%201%2019%20final%20WERB-
approved%20%28NIST%20vers%2011-18-2019%29%2B.pdf
Online, Available: https://www.nist.gov/system/files/documents/2019/05/09/ps_2-18_final_apr_2019_dfa_reviewed.pdf
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3.2.8.1 Discussion—
Table X1.1 provides summary information for the walls evaluated to represent the reference shear wall system.
3.2.9 seismic equivalence parameters (SEP), n—key parameters representing seismic performance of shear walls, specifically drift
capacity, component overstrength, ductility, and maintenance of vertical-load-supporting capability.
3.2.10 shear wall, n—wall designed to resist lateral racking shear forces parallel to the plane of the wall.
3.2.11 shear wall configuration, n—shear wall of a specific height and length representing one possible case of a shear wall system
and consisting of a specific arrangement of components, such as framing, fasteners, sheathing, and anchorage.
3.2.12 wood structural panel (WSP)—panel manufactured in accordance with PS1 or PS2 from veneers; wood strands or wafers;
or a combination of veneer and wood strands or wafers; bonded together with waterproof resins or other suitable bonding systems.
4. Summary of Practice
4.1 Shear walls are tested in accordance with Test Methods E2126, and the average envelope curve is generated for each specimen
as defined in 3.2.4 of Test Methods E2126.
4.2 SEPs are determined from the average envelope curve for each specimen, and the average SEPs for each tested shear wall
configuration are compared to the benchmark parameters.
4.3 Seismic equivalency is established if each of the SEPs for the alternative shear wall system meets specified requirements and
the vertical-load-supporting elements are intact and capable of supporting gravity loads.
5. Significance and Use
5.1 This practice documents cyclic performance benchmarks for shear walls constructed with wood structural panel (WSP)
sheathing attached to dimension lumber framing using common or galvanized box nails as defined in 3.2.8.
5.2 Procedures described in this practice provide a method to evaluate an alternative shear wall system’s SEPs to demonstrate
equivalent in-plane lateral seismic performance to the reference shear wall system.
5.3 The procedures described in this practice do not address all factors to be considered for recognition of an alternative shear wall
system. Such factors, as described in 1.4, vary by the end-use application and shall be addressed outside the scope of this standard
through an evaluation of the acceptability of the alternative shear wall system in accordance with requirements of building codes
and standards, as applicable.
6. Testing Requirements
6.1 Test Program Design—The test program used to evaluate the alternative shear wall system shall be based on consideration of
the range of intended applications and variables that have a potential impact on the seismic performance. Variables may include,
but are not limited to, allowable design loads, configuration options, material variations, overturning restraint types, fastener
spacings, and aspect ratios.
6.2 Number of Tests—For each tested shear wall configuration, the number of replicates shall be as required in 8.1 of Test Methods
E2126 or as required by the applicable product standard.
6.3 Loading—Cyclic lateral load tests shall be conducted using Method C from Test Methods E2126.
6.3.1 Load Beam—The load beam used to apply load to the test assembly shall comply with 7.3.1 of Test Methods E2126.
6.4 Rigid Base—Testing shall be conducted on a rigid base, such that the performance of the test specimens is not influenced by
deformation of the base structure. The specimens shall be anchored directly to the base and shall be in full contact with the base.
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6.5 Test Specimen Construction—Specimens shall be constructed using details consistent with the intended application. Sheathing,
if present, shall not bear on any portion of the test fixture or the loading beam during the tests, except where the specified end-use
installation requires the sheathing to bear on supporting elements, such as foundations or sill plates. If bearing on a wood sill plate
is specified in application, a similar wood sill plate shall be included in the tested assembly.
6.5.1 Aspect Ratios—Aspect ratios and wall dimensions shall be consistent with the intended application.
6.5.1.1 Alternative shear wall systems that are similar to the reference system (that is, repetitive vertical stud framing spaced at
24 in. on center or less with structural sheathing nailed to framing), except for variations in framing materials, sheathing materials,
or fasteners, shall be evaluated using an aspect ratio of 1:1 and a minimum wall height of 8 ft (2.4 m).
6.5.1.2 Alternative shear wall systems that vary more significantly from the reference system described in 6.5.1.1 shall be
evaluated using the range of aspect ratios for the intended application.
6.5.2 Sheathing Joints—Alternative shear wall systems that will include discrete sheathing panels shall include at least one vertical
sheathing joint if such joints will occur in application. Test specimens may include horizontal sheathing joints as necessary, such
as where specimen heights exceed panel height or where sheathing is intended to be installed with the long dimension
perpendicular to the longitudinal axis of the studs.
6.5.3 Framing—Where applicable, the stud and plate material, species, grade, size, and spacing shall be representative of that used
in application. Framing shall meet the requirements of 6.3 in Test Methods E2126.
6.5.3.1 For alternative systems described in 6.5.1.1, framing with the smallest standard stud and plate cross sections expected in
application shall be used, and the smallest number of end post studs that can practically be employed in accordance with standard
design provisions shall be used.
6.5.4 Anchorage and Framing Connections—Shear anchorage, overturning restraint, and framing connections, including
connections between individual plies of built-up posts, shall be representative of typical connections used in application and shall
be designed and detailed to optimize to the extent practical the design resistance of the connections to the design load of the shear
wall.
6.5.4.1 Alternative systems described in 6.5.1.1 shall be tested with bolts for shear anchorage and eccentric-type hold downs
positioned inside the wall for overturning restraint unless use of an alternative shear anchorage or hold down system, or both, will
be required in application. Where either an alternative shear anchorage or overturning restraint is required in application, the
specified alternative shall be permitted for the evaluation.
6.5.5 Sheathing Connections—Where sheathing attached to framing is used to resist lateral loads, the sheathing fasteners shall be
installed using the minimum edge distance recommended by the sheathing manufacturer along all four sheathing edges. The
number of fasteners installed along each edge shall be equal to the length of the sheathing edge divided by the specified fastener
spacing, plus one. Spacing between the sheathing corner fastener and the next adjacent fastener is permitted to be less than the
recommended spacing to accommodate the required edge distance. Sheathing fasteners placed in the field of the panel, if any, shall
be positioned as required by the design. Sheathing fasteners shall be driven so that the head of the fastener contacts the surface
of the sheathing, but not so deep as to crush the surface, unless specified differently by the manufacturer.
7. Evaluation of Cyclic Response
7.1 Average Envelope Curve—The average envelope curve shall be generated for each test specimen as defined in 3.2.4 of Test
Methods E2126.
7.2 SEP Determination—The component overstrength, drift capacity, and ductility shall be determined for each specimen as
defined in 3.2. The average values calculated for all replicates of a tested shear wall configuration shall be the SEPs for the
alternative shear wall configuration. The results of multiple shear wall configurations shall not be averaged or otherwise combined
for the evaluation.
7.3 Assessment of Vertical-Load-Supporting Elements—The condition of the vertical-load-supporting elements shall be visually
assessed to qualitatively determine whether the capability to support gravity loads is retained.
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NOTE 1—Visual assessment of vertical-load-supporting elements relies on examination during and after the test for observation of occurrence of buckling
of the vertical-load-supporting elements. failure modes, such as buckling, that compromise the wall assembly’s ability to carry vertical load. For
wood-frame walls that comprise the reference shear wall system, the lack of observed buckling of or other significant vertical load limiting failure modes
for the studs and end posts has been used as visual confirmation of retained ability to support gravity loads.
8. Requirements for Equivalency
8.1 Table 1 provides the SEP performance targets based on tests of the reference shear wall system conducted in accordance with
Method C of Test Methods E2126.
8.2 Seismic equivalency is established if the SEPs for the alternative shear wall system meet requirements specified in Table 1
and if the vertical-load-supporting elements are judged to retain capability to support gravity loads.
9. Keywords
9.1 cyclic loads; earthquake, shear wall; lateral force; seismic; wood structural panel;
APPENDIX
(Nonmandatory Information)
X1. COMMENTARY
X1.1 Introduction
X1.1.1 Shear walls constructed with wood structural panels (WSP) fastened to sawn lumber framing with common or galvanized
box nails are widely used in construction. This system serves as the reference shear wall construction for this practice. When
subjected to cyclic loads, this reference system demonstrates desirable ductile yield modes with significant drift capacity, ductility,
and overstrength. The seismic design provisions for engineered light-frame wood construction in North America account for this
behavior by assigning appropriate seismic design coefficients. These coefficients are used to determine the seismic design loads
on a structure and to estimate the building response to an earthquake.
X1.1.2 As new structural systems are developed or modifications to the reference system are introduced, the seismic response
capabilities of the new or modified systems are often questioned. For example, will the response of the alternative system be
significantly different from the benchmark system or will the use of a proprietary sheathing panel, fastener, or framing material
fundamentally change the seismic response of the benchmark wall system? Can an entirely new wall system or product be
intermixed with the benchmark system and behave in a compatible fashion? This practice provides a relatively simple, quantitative
method for comparison of cyclic resistance parameters to establish seismic equivalence. However, there are many considerations
beyond the results of the in-plane lateral tests performed in accordance with this practice for evaluation of SEPs that must be
considered before a new system can be deemed equivalent to the reference system for all aspects of building performance in a
seismic event. For this reason, it is required for the alternative shear wall system to have documentation, such as a product standard,
TABLE 1 SEPs for Equivalency to Nailed, Wood-Frame, WSP Shear Walls
Parameter SEP Requirement
P
peak, avg
Component Overstrength
2.5# #5.0
P
ASD
Drift Capacity
Δ $0.028h
U, avg
Δ
U, avg
Ductility
$11
Δ
ASD, avg
P = average peak load for all replicates of the wall configuration,
peak, avg
P = allowable design load for the wall configuration,
ASD
Δ = average ultimate displacement for all replicates of the wall configuration,
U, avg
h = height of the shear wall, and
Δ = average displacement corresponding to the allowable design load for all replicates of the wall configuration.
ASD, avg
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that addresses the specific issues listed in 1.4, as well as any other relevant issues necessary to the use of the product. Assessing
all aspects of seismic performance for the end use application is beyond the scope of this standard.
X1.2 Development of Equivalency Procedure
X1.2.1 In 2007, an ICC Evaluation Service task group was formed to create an approach for a new structural system to
demonstrate seismic equivalence to wood-frame WSP shear walls (1, 2). This task group included consulting engineers, academics,
trade association representatives, product manufacturers, and wood industry professionals. The initial focus of the group was to
derive a procedure that could be used to judge whether high-aspect-ratio, prefabricated shear panels could be assigned the seismic
design coefficients and factors associated with the WSP reference system.
X1.2.2 Several different quantitative parameters from cyclic shear wall testing were reviewed by the industry task group to
represent the seismic performance of the reference system (1, 2). Ultimately, they selected drift capacity, component overstrength,
and ductility, as defined in this practice, to represent seismic performance for the reference system.
X1.2.3 In addition, the task group observed that degradation of the sheathing and fasteners under progressive cyclic lateral loading
does not typically compromise the ability of the wood studs in the reference system to support vertical loads. Therefore, in the
absence of a consensus standard to conduct combined vertical and lateral load testing, it was determined that alternative systems
should also demonstrate this characteristic (1, 2). Examples of failure modes that could be induced in a lateral load only test that
would inhibit the ability to carry a simultaneous vertical load might include buckling, bending or compression fracture of a
non-redundant assembly, or similar failure for multiple framing members within light-frame assembly. Given the wide variety of
potential wall assemblies that might be reviewed under this protocol, it is not possible to prescriptively list acceptable and
unacceptable failure modes and some practical engineering judgement and rationalization is required for this qualitative
assessment. Alternative systems that demonstrate significant degradation of the vertical-load-supporting elements during the lateral
load test or exhibit questionable failure modes cannot achieve equivalence through this protocol alone.alone and some form of
combined load testing should be considered.
X1.2.4 It is an underlying assumption of this procedure that an alternative shear wall system judged to be equivalent through this
practice may either be used alone or in combination with wood-frame shear walls sheathed with wood structural panels. The
potential for use in combinati
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