TM 5-822-11/AFP 88-6, Chap. 7
b. If the sealant is to be placed in a pavement
used to remove all of the sealant residue from the
feature which will be subjected to jet fuel or
sides of the sealant reservoir after the old joint
hydraulic fluid spillage, the sealant should be a
sealant has been removed. The removal of the
JFR type. Pavement features that will be subjected
sealant residue will provide a clean surface to
to fluid spillage include aprons, hardstands, and
allow the new sealant to bond to the concrete joint
washracks. Likewise, if the sealant is to be placed
faces. The existing sealant must be removed com-
in a pavement feature that will be subjected to jet
pletely from the joint sidewalls, but it only has to
blast, the sealant should be resistant to jet blast.
be removed to a depth that will allow the new
Features that are subjected to jet blast include
sealant to be installed with the correct shape
runway ends and warmup or holding pads.
factor. Special care must be taken to ensure that
c. The condition of the joints must be
the existing sealant is completely separated from
considered when selecting a sealant. Joints with
the new sealant. This is accomplished by using a
spalling require more extensive repair before
separating tape or a backer material.
resealing with a preformed elastomeric
b. Only medium- or high-severity cracks in
compression seal than they would when resealing
concrete pavement should be sealed. It is difficult
with a field-poured sealant.
to properly seal low-severity cracks in concrete
d. The performance history of different sealants
pavement due to the width of the crack; therefore,
at the installation should be examined and if
they should not be sealed. Most high-severity
enough information is available, the past perfor-
cracks will require some type of repair before
mance can be used to prepare an actual life-cycle
sealing. All severity levels of cracks should be
cost of the sealants. A life-cycle cost should also
sealed in bituminous pavement.
be performed to determine which procedures and
c. Both in-house crews and contractors can per-
sealants are best suited for providing the most
form sealing projects. Sealing by in-house crews
cost-effective solution over the life of the feature
is limited by availability of equipment, man-hours
being sealed. Appendix D contains a procedure for
available, and trained personnel. Therefore, in-
performing these analyses. One of the major
house crews normally handle routine spot sealing,
drawbacks of life-cycle cost analysis at the present
and larger projects are contracted out.
time is the lack of information on the field
d. When in-house crews perform routine spot
performance of sealants.
sealing, the new sealant must be compatible with
the existing sealant. For example, asphalt based
3-6. Selecting Sealing Procedures.
sealants should be used when the existing sealant
a. The present condition of the joint sealant
contains asphalt. Tar based sealants should be used
reservoir and the type of sealant selected will
when the existing sealant contains tar. Sealants
determine the sealing procedures. The joint shape
that contain coal tar should not be used in asphalt
factor must provide enough width to allow the
pavement, and sealants that contain asphalt should
working range of the sealant to exceed the hori-
not be used in tar pavement. The existing type of
zontal movement of the joint. If the joint is not
sealant can usually be found in construction
wide or deep enough to meet the shape factor
records. If there is any question about the type of
requirements, the joint sealant reservoir must be
in-place sealant, sealants made with coal tar can
enlarged by saw cutting. If the existing shape
usually be identified in the field by their
factor is adequate, only cleaning is required.
distinctive coal tar (creosote) odor. Table 3-3
Sand-blasting, high pressure water stream (water-
provides guidance on the compatibility of various
blasting), or other approved procedures must be
sealants.
3-5
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