Remote Health Monitoring for Asset Management

several days. Temperatures increase slightly into the sound soil, as the pile is not driven very
deep due to the bedrock present at the site.
15
55
TEMPERATURE (ºC)
10
5
0
-5
-10
-15
Sound earth
Transition
Air
45
35
Initial
25
Low temp.
High temp.
15
5
0 50 100 150 200
HEIGHT (in.)
TEMPERATURE (ºF)
Figure 5.14. Temperature profile along the test pile for high, low and initial air temperatures.
To further investigate the location of the air/soil interface on the installed pile, the pile was
locally heated with a torch at the air/soil interface. The pile is installed along an inclined bank,
such that the air/soil interface is different on opposing sides of the pile as shown in Figure 5.15.
Heat was applied to the pile at the downhill location (location A) to heat the pile locally, such
that the sensor that responded to the applied heat could be identified. The distribution of heat
along the length of the pile is shown in Figure 5.15. Heat was also applied, though for a shorter
time, to the up-hill side of the pile (location B), directly heating the armor channel holding the
sensor. A smaller amount of heat was applied at location B to avoid damaging the epoxy in
which the sensors are embedded. The spike in temperatures at location A and B can be clearly
seen in the pile profile in Figure 5.15. The data indicated that sensor 24, located at a height of 69
in., was closest to applied heat at location A. At location B, sensor 27, at height of 78 in along
the pile, was closest to the applied heat.
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