TM 5-6635-386-12&P
Tester will commence slow "beep" during count.
Para 1-7 describes the use of a ratio for determination of
the final values, the ratio serving to cancel out long term
e. Tester will "beep-beep" fast at end of count.
drifts from source decay or component aging.
Press DENSITY DATA or MOISTURE DATA key to
It is now necessary to record the field count data and to
read count from tester.
divide that data by the recorded standard count to obtain
the desired ratios. The ratios will then be taken to the
Record this on the Field Data Worksheet.
answers.
NOTE
(CPN) with the tester. The charts are also titled to
DA Form 5450-R (Moisture and Density Field
indicate the purpose of each chart; backscatter density,
Test Sheets) (an abbreviated version of DA
backscatter-moisture, transmission at "2", etc. The
Form 5448-R) can be found at the back of this
charts are also identified with a serial number which
TM.
matches the serial number of the tester. Charts and
testers are not interchangeable.
Moisture is taken at all times during any density
count The moisture source is separately mounted within
RATIOS
DENSITIES
the tester. Only the density source is in the source rod.
The moisture reading taken in the BS position is
0 246
127.00
recorded on the worksheet.
0.243
127.50
0.240
128.00
f. If a density only or moisture only count is
0.238
128.50
required, press the D-ONLY or M-ONLY keys to take
0.235
129.00
only the desired count. The other prior count will be
0.232
129.50
saved in memory.
Figure 1-8.
1-22.
FIELD
COUNTS,
TRANSMISSION
AND
MOISTURE
NOTE
a. Site is prepared, standard count recorded, hole
The ratios listed in the left column cross over to
drilled.
the densities listed on the right. For example,
the ratio 0.240 crosses over to 128, which is the
b. Seat tester over hole and insert source per Para
density in pounds per cubic foot weight (PCF). If
1-19.
the ratio was calculated to be 0.239, which is not
listed, the ratio would then have to be rounded
c. Insure that handle is firmly in the desired depth
up or down (usually down) to the closest listed
slot.
ratio so the density can be determined.
d. Firmly pull tester back against the hole to seat
The following portion of DA Form 5448-R (Fig. 1-9)
the source against the hole wall.
provides data for a typical density test using a tester at
three sites on a project and with three depths taken at
e. Depress the desired time key.
each site. The average of the three readings will be
used as the final evaluation density for the project.
f. Record the data from density data displays.
1-23. DETERMINE DENSITY AND MOISTURE FROM
CALIBRATION CHARTS
1-17