ASTM C1392-00(2009)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: C1392 − 00(Reapproved 2009)
Standard Guide for
Evaluating Failure of Structural Sealant Glazing
This standard is issued under the fixed designation C1392; 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 program.The authority’s qualification level that is necessary to
specify the evaluation criteria and interpret the significance of
1.1 This guide covers a screening approach to detect failure
the results depends upon the level of sophistication of the
(adhesive or cohesive) of a structural sealant in a structural
evaluation program. For example, if statistical and finite
sealant-glazed window, curtain wall, or other similar system.
element analyses are being incorporated into the evaluation
Presently, only a silicone-sealant that is specifically
program, then the authority should be knowledgeable and
formulated, tested, and marketed as a structural glazing sealant
experienced in these areas.
is allowed for structural sealant glazing.
3.1.2 competent person, n—a person experienced in the
1.2 The values stated in either acceptable metric units or in
operation of the testing equipment and with an understanding
other units shall be regarded separately as the standard. The
of the construction of the wall system. This person may carry
values stated in each system may not be exact equivalents;
out the field testing under the supervision of the qualified
therefore,eachsystemmustbeusedindependentlyoftheother,
authority.
without combining values in any way.
4. Summary of Guide
1.3 There are no ISO standards similar or equivalent to this
4.1 This guide uses deflection measurements obtained from
ASTM standard.
localized applied loads to determine locations of sealant failure
1.4 This standard does not purport to address all of the
in an installed structural sealant glazing system.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 4.2 Initially, the deflection of an existing lite that is fully
priate safety and health practices and determine the applica- adhered by a structural sealant is measured when a discrete
bility of regulatory limitations prior to use. edge of the lite is loaded laterally. Subsequently, at a few
selected lites, the structural sealant is cut intentionally to
2. Referenced Documents
simulate failure, and the deflection of the lite is measured at the
same lateral load. This provides the basis for determining
2.1 ASTM Standards:
during subsequent tests of other lites in the system whether the
C717 Terminology of Building Seals and Sealants
sealant has failed.
3. Terminology
4.3 Additional lites are evaluated and their deflections
3.1 Definitions: Refer to Terminology C717 for the follow-
measured to determine the extent of any structural sealant
ing definitions and description of terms used in this guide:
failure. Structural sealant failure is determined by comparing
adhesive failure; cohesive failure; deflection; glazing; joint;
the measured deflections with the initial measurements of
lite; modulus; silicone sealant; structural sealant; structural
deflection with and without failed (intentionally cut) sealant.
sealant glazing; and substrate.
5. Significance and Use
3.1.1 qualified authority, n—a person with a recognized
degree or professional certificate and extensive knowledge and
5.1 This guide suggests a simple means of evaluating the
experience in the particular fields necessary for the evaluation extent of any failure of a structural sealant in an installed
structural sealant glazing system.
5.2 A qualified authority should specify the criteria de-
ThisguideisunderthejurisdictionofASTMCommitteeC24onBuildingSeals
scribed in Sections 8 and 9 and should interpret the results and
and Sealants and is the direct responsibility of Subcommittee C24.10 on
Specifications, Guides and Practices.
judge their significance for the structural sealant glazing
Current edition approved Dec. 1, 2009. Published December 2009. Originally
system.
approved in 1998. Last previous edition approved in 2005 as C1392 – 00(2005).
DOI: 10.1520/C1392-00R09.
5.3 The evaluation program measures deflection of loaded
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
lites and does not measure directly any structural sealant
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
failure. Consequently, the qualified authority interpreting the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. datashouldalsoevaluatethesourceofanyincreaseddeflection
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1392 − 00 (2009)
that is measured. Increased deflection may be due to structural 8. Establishing Deflection and Sealant Failure
sealant adhesive or cohesive failure, but may also be due to a Relationship
decrease in sealant modulus, a change in sealant joint
8.1 Summary of Procedure—Establishing the deflection/
dimensions,orothernonfailuremechanisms.Selectivedestruc-
failure relationship requires the specifying authority to select
tive sampling of areas with increased deflections can assist in
the applied load magnitude, the locations of the applied loads
this evaluation.
on the lite, and the criteria for failure length. The following
describes various approaches that can be used to select these
6. Suggested Apparatus
parameters, depending upon the sophistication of the evalua-
6.1 Field Loading Device, provides a frame that can span
tion program and the desired results. Depending upon the
beyond the edges of the loaded lite, while supported by suction
parameters selected the procedure can be used as a crude
cups on the face of adjacent lites or by other means that do not
screening tool or can be correlated to the actual stresses within
adversely affect the stresses in the tested structural sealant and
the structural sealant joint under an applied load and used as a
lite (Fig. 1 and Fig. 2). To permit application of a force
rational means of assessing areas of failure that require repair.
perpendicular to the surface of the lite, mount a loading piston
Using the deflection magnitudes and locations, the initial
on the lite, with a suction cup or other means near the edge of
evaluation establishes the relationship between loaded lite
thelite.Placealoadcellbetweenthesuctioncupandtheframe
deflections with intact structural sealant and those with failed
to monitor the applied load. Calibrate the field loading device
structural sealant.
and the load cell prior to use on a project and immediately after
8.2 Applied Load Magnitude—The qualified authority
any changes or damage to the device.
specifies the magnitude of the applied load.The load should be
6.2 Deflection Measurement Device, either an extensometer
large enough to produce significant differences in deflection
with a dial gage mounted on an adjacent lite or a straight edge
between intact and failed sealant areas, that is, the failure
with feeler gages, of length equal to the length of the edge of
length criteria. The applied load can be derived from the
the lite. The device should be accurate to within 10 % of the
glazing system’s lateral design loads through computer mod-
measured deflection.
eling (finite element analysis), if it is necessary to relate the
testing to a design load and stress.
7. Sampling
8.2.1 An initial evaluation will determine whether the ap-
7.1 The qualified authority should specify the locations,
plied load is large enough to produce significant differences in
distribution, and number of applied loads for the structural
deflectionbetweenareaswithintactstructuralsealantandthose
sealant glazing system. Sections 8 and 9 discuss various
with failed structural sealant. Excessive loads may crack the
approaches to this selection process.
glazing material.
8.3 Applied Load Locations on a Lite—The evaluation
procedure involves application of a local load to a discrete
portion of the edge of a lite. Therefore, a single application
doesnotnecessarilyevaluateastructuralsealantjointalongthe
entire edge of a lite. The stress distribution in the structural
sealant from the applied load is a function of many variables,
including the relative stiffness of the sealant and glazing
material, the location of the suction cup, and any resistance
from setting blocks or similar items. The qualified authority
should specify the extent of testing that is appropriate along
each edge of a lite.This determination can be
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