meric compound, however, is a temperature range
ignored by sealant researchers, although there have
for which rubber-like behavior occurs. As the
been recommendations within the sealant research
temperature of an elastomer is decreased, its me-
community that conventional practices of struc-
chanical behavior changes until it behaves like
tural mechanics be used to study and specify the
glass. This is a phenomenon that can cause seals
behavior of sealants. In the related field of rubber
to stiffen during cold periods. Very few data exist
and elastomers it is conventional practice to con-
in the literature or in manufacturers' specifica-
duct material property tests, as a function of tem-
tions concerning sealant properties as a function
perature, and to use the information obtained to
of temperature, although in the rubber and poly-
conduct structural analysis. In all of structural en-
mers industry such material property data are
gineering research it is also conventional to vali-
routinely generated for evaluating the effective-
date the results of analysis with tests of model struc-
ness of a material. Without such data, or without
tures. This classic framework should be applied
extensive practical experience, seal designers can-
in the research of sealants and joint seals, and
not independently know the temperature below
should be followed to study sealants for cold cli-
which a sealant will perform inadequately. For a
mate applications. As indicated in this review, phe-
particular cold region application, performance
nomenological theories of material behavior, ma-
tests conducted at a single low temperature, which
terial property tests, structural analysis methods
is a typical condition implemented in standard
and structural testing capabilities are available for
test methods, do not in general provide enough
adopting this framework. For the development of
information for an engineer to establish the effec-
selection and design criteria for cold climate seal-
tiveness of a sealant.
ants and seals, this approach, as compared to the
Previous experimental studies of the mechani-
conventional performance testing approach, would
cal behavior of joint and crack sealants have re-
be most efficient and productive.
lied primarily on structural configuration perfor-
mance tests rather than material property tests to
obtain measures of the sealant response. Although
LITERATURE CITED
structural configuration tests can reveal system
properties, properties reflecting the stress and
ACI (1993) Guide to sealing joints in concrete struc-
strain behavior of the material cannot be found
tures, ACI 504R-90. In ACI Manual of Concrete Prac-
from these tests. Structural tests are generally con-
tice. Part 5. Detroit, Michigan: American Concrete
ducted using block-shaped model seal specimens
Institute.
constrained between parallel surfaces of a given
ASTM (1991a) Standard definitions of terms re-
substrate. These tests have been developed pri-
lating to building seals and sealants. C 717-87a.
marily to provide a basis for quantifying the ca-
Annual Book of ASTM Standards, Vol. 4.07. Phila-
pability of the seal to withstand the movements
delphia, Pennsylvania: American Society for Test-
of seasonal joint opening and closing. There is con-
ing and Materials.
fusion in the sealant literature regarding the na-
ASTM (1991b) Standard terminology relating to
ture of tests on model seals, however. Of greatest
rubber. D 1566-88. Annual Book of ASTM Standards,
concern is that research test results of model seals
Vol. 9.01. Philadelphia, Pennsylvania: American So-
are often reported as if a homogeneous material
ciety for Testing and Materials.
response rather than an inhomogeneous struc-
ASTM (1991c) Standard practice for determining
tural response has been measured. This lack of dis-
and reporting dynamic mechanical properties of
tinction between the response of the material and
plastics. D 4065-82. Annual Book of ASTM Standards,
the response of the structure formed from the ma-
Vol. 8.03. Philadelphia, Pennsylvania: American So-
terial has led to a conventional practice in which
ciety for Testing and Materials.
butt joint seal structures are tested not only to as-
ASTM (1991d) Standard test methods for rubber
certain the behavior of a particular structure, but
properties in tension. D 412-87. Annual Book of
also to specify the behavior of the sealant mate-
ASTM Standards, Vol. 8.01. Philadelphia, Pennsyl-
rial, and to do so without suggesting that the be-
vania: American Society for Testing and Materials.
havior is the apparent material behavior for the
ASTM (1991e) Standard methods of testing joint
particular structure. Structural and experimental
sealants, hot-poured, for concrete and asphalt pave-
analysis conducted more than 30 years ago clear-
ments. D 3407-78. Annual Book of ASTM Standards,
ly showed that this practice can be misleading.
Vol. 4.03. Philadelphia, Pennsylvania: American So-
Structural analysis, for the most part, has been
ciety for Testing and Materials.
18
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