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