Figure 11. Residential sewer line crossing through the shield.
was installed in the basement of a house on
tween the sewer pipe and the insulation, as shown
Labossiere Street. This house is about 110 m (360
in Figure 11.
ft) up the street and about 37 m (120 ft) from our
The shield was constructed in the manner de-
main test section. We also installed water flow
scribed above up to the end of the line at approxi-
meters in the pipe at two locations but were dis-
mately 127 m (417 ft). It would have been desir-
appointed to discover that both failed to function
able to run the insulation shield 1.5 to 3 m (5 to 10
properly. Figure 7 is a profile view of the as-built
ft) past the end of the pipe, but ledge prevented
pipeline with several points of interest marked.
this. The installation of the shield was not the
Three immersion thermocouples were installed
limiting factor in the speed of the pipe laying; the
into the pipe at 3.1, 73, and 125 m (10, 240, and
ledge blasting and removal took considerably
410 ft) from the beginning of the insulation. These
longer than the time needed to install the insula-
allow us to monitor the water temperature as it
tion. Backfilling was slowed slightly by the extra
progresses up the street. At our main test site we
care taken around the insulation sides, but this
have also installed thermocouples around the out-
time was minimized after we gained confidence
side of the pipe near the middle immersion ther-
in the ability of the jigs to keep the insulation
mocouple. This will allow us to tell if there is any
from moving during the process.
significant difference between the temperatures
of the water and the outside of the pipe.
The bottom immersion thermocouple gives us
INSTRUMENTATION LAYOUT
the temperature of the water near the entrance of
the test pipe. This will be a baseline temperature
The general experimental plan called for moni-
of the water as it enters the test section, before
toring temperatures at several points along the
any influence of the shield. A flow meter was
pipe with thermocouples, detailed below, as well
installed at 6.1 m (20 ft) up the pipe but, as men-
as an extensive thermocouple layout at a test sec-
tioned before, it is not working properly. We had
tion about 73 m (240 ft) up the pipeline. In this
hoped to know the water flow into the test sec-
application we used copper/constantan, type T
tion by this meter. Another thermocouple was
thermocouples. The temperature data is automati-
cally recorded by a Fluke 2286 datalogger that
placed on the outside of the pipe at about 24.4 m
10
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