TM 5-822-11/AFP 88-6, Chap. 7
sealant to fail prematurely in the same manner as
table 3-1, to show the overall condition of the
the previous sealant. Examples of possible causes
joint sealant. The relative amounts of each level of
of premature sealant failure may include but are
severity present can be recorded to show the
not limited to incorrect sealant reservoir shape
variability of the joint seal damage.
factors, excessive vertical movement or too large
c. Determine Joint or Crack Condition. The
of a working range at the joint, and improper
condition of the joints or cracks is recorded as the
sealing techniques used during sealant installation.
percentage of slabs with the specified severity of
spalling. The data for severity of spalling are used
3-3. Condition Survey.
to determine the existing pavement condition. The
a. The pavement must be surveyed according to
general condition of the pavement feature being
the procedures in TM 5-826-6/AFR 93-5 to deter-
evaluated and the secondary factors of environ-
mine the current condition of the sealant, the joint
ment and soil type which influence joint sealant
and crack condition, moisture related distress
performance must be recorded. The data provide
types, and the overall pavement condition. Field
the information needed to evaluate sealant needs
measurements may be required to determine the
and function. Historical data and future use are
existing joint shape factor. The measurements
recorded to provide an indication of past perfor-
should be made during the condition survey by
mance and future requirements of the sealant and
physically removing some of the old sealant and
feature. The data collected can be presented on the
recording its shape and hardness. Tables 3-1 and
pavement evaluation checklist shown in table 3-2.
3-2 contain the items that should be collected to
3-4. Evaluation to Justify Sealing
allow evaluation of the sealant and pavement.
Work. After the survey data and other factors
affecting sealant performance have been collected,
it must be evaluated. The results from the analysis
will determine if resealing is justified. The
checklists shown in tables 3-1 and 3-2 provide the
step-by-step approach to the evaluation. The fol-
lowing guidelines indicate the relative need to seal
a given pavement based upon the ratings obtained
from the checklists. The overall sealant ratings are
given in the following paragraphs.
a. Excellent to Very Good (0 to 1). Resealing
b. Determining Sealant Condition. The proce-
is not required. Some routine sealing may be
dures in TM 5-826-6/AFR 93-5 rate the average
needed in localized areas of high-severity damage.
joint condition within each sample unit at a low-,
medium-, or high-severity level. A more accurate
b. Good to Fair (1 to 2). Resealing can be
but more time-consuming method would be to rate
considered. Any of the following items would
the sealant condition in each joint as the survey is
indicate that remedial action should be considered
conducted. In either case, the overall joint sealant
to prevent the distress from progressing.
condition rating may be calculated using the fol-
(1) A moisture susceptible subgrade and an-
lowing equation:
nual rainfall of more than 15 inches or a monthly
rainfall of more than 3 inches.
Rating = [(%L)(1.0) + (%M)(2.0) + (%H)(3.0)]/100.0
(2) More than 10 percent of the slabs with
where
medium or high-severity joint and corner spalls.
%L
= percent of sample units having low severity joint
(3) Evidence of incompressibles in the joints.
seal damage or percent of total length having low
(4) More than 10 percent of the slabs with
severity joint seal damage.
medium or high-severity faulting.
%M
=
percent of sample units having medium severity
(5) More than 30 percent of the deduct values
joint seal damage or percent of total joint length
caused by moisture accelerated distress types.
having medium severity joint seal damage.
(6) Significant or potential FOD problems
%H
=
percent of sample units having high severity joint
due to spalling joints or cracks have developed.
seal damage or percent of total joint length having
(7) More than 30 percent of the joint sealant
high severity joint seal damage.
damage is at a high-severity level.
The equation produces a rating from 0 to 3 that
(8) The change in the PCI when calculated
indicates the general condition and can be pre-
assuming no joint seal damage present is signifi-
sented on a condition rating scale, as shown in
cant.
3-3
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