100
80
60
Central Wisconsin Airport
40
Transverse Joints
Location 27
Location 26
20
Location 24
Location 23
0
15
20
25
30
5
10
15
20
25
Mar
Apr
Figure 42. Change in transverse joint transfer with time on taxiway B.
3. With a few exceptions, as shown in Tables 11b
worthy (1985) (Fig. 40). In addition, we determined
and 12b, the JTE was low across the longitudinal
that increases in temperature did not cause increases in
joints at CWA and OCA. The data infer that, in gener-
JTE during the early thaw period; the JTE in most cas-
al, the longitudinal joints were weak with respect to
es decreased. As thaw progressed, the JTE recovered.
load transfer.
In the late thaw period, the JTE was basically a linear
The LTE was determined for the transverse joints
function of temperature (Fig. 40b). The most signifi-
both at CWA and OCA using the procedure outlined
cant effect of thawing was related to the basesubgrade
in Hammons and Pittman (1993). The LTE across a
modulus (Fig. 41).
joint is estimated as a function of the radius of relative
2. At the CWA FWD locations where the base
stiffness (l) and the JTE. The JTE is determined from
course was 1.2 m thick, the effect of temperature on the
FWD deflection data as discussed above. The radius
transverse joint efficiency was negligible (Fig. 42). It
of relative stiffness (l) is determined from the normal-
should also be noted that the thickness of the PCC layer
ized basin area (AREA) from a unique relationship de-
is 330 mm compared to the other sites, where it ranged
veloped by Ioannides (1989). This relationship for a
from 254 to 305 mm. This increase in thickness may
dense liquid foundation is reproduced in Figure 43. A
also contribute to the negligible effect of surface tem-
sixth-order polynomial equation was developed for
perature on the JTE. This was not observed at OCA.
100
Dense Liquid Foundation
a = 5.9055
80
60
40
20
0
15
20
25
30
35
Area (in.)
Figure 43. Relationship between AREA and l for a dense liquid foun-
dation, a = 5.90655 in. (after Hammon and Pittman 1993).
35
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