TM 5-822-11/AFP 88-6, Chap. 7
(1) The joint or crack must be visibly dry
sealants are highly temperature dependent. Cool
before sealing is allowed to proceed. Visible mois-
temperatures increase the amount of time it takes
ture includes rainfall and even a heavy dew which
for the sealant to cure. A good seal can normally
may produce condensation on the pavement. If the
be obtained when the sealant finally cures, but the
moisture is not allowed to fully evaporate before
sealant will remain tacky for an excessively long
the sealant is applied, the sealant may not ade-
period of time. While the sealant is still tacky, it
quately bond to the joint face leading to adhesion
can be pulled out of the joint by traffic and
failure.
tracked onto the pavement surface. When the
(2) The temperature of the concrete and
sealant does cure and develop bonding strength,
the ambient temperature will influence the bonding
there may not be enough sealant remaining in the
of hot-applied sealants to the concrete and can
joint to maintain the required shape factor and
retard the curing of cold-applied sealants. A
performance will suffer.
general recommendation is that the air and
d. Sealant Type Location. It is possible that two
pavement temperature be 50 degrees Fahrenheit
different sealant types, JFR and non-JFR, hot-
(35 degrees Fahrenheit) and rising before sealant
applied and cold-applied, or field molded and pre-
application is allowed. If the joint walls are too
formed, may have to be applied during the same
cold, they will chill the hot sealant as it is applied.
sealing project if the contract overlaps different
This chilling prevents the sealant from developing
pavement features. These features must be clearly
intimate contact with the concrete and filling all
noted on the plans and should be indicted on the
the pores on the joint surface which develops the
pavement sections. The equipment operators and
bond between the sealant and the concrete.
all personnel involved with inspection should
Adhesion failures are more likely to develop when
know the areas where sealant types change and
a hot-applied sealant is placed in cool weather.
should physically verify these locations before the
(3) The curing of some cold-applied
beginning of the project.
5-5
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