1-22. FIELD COUNTS, TRANSMISSION AND MOISTURE

TM 5-6635-386-12&P Tester will commence slow "beep" during count. e. 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. NOTE 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 TM. 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. f. 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. 1-22. FIELD COUNTS, TRANSMISSION AND MOISTURE a. Site is prepared, standard count recorded, hole drilled. b. Seat tester over hole and insert source per Para 1-19. c. Insure that handle is firmly in the desired depth slot. d. Firmly pull tester back against the hole to seat the source against the hole wall. e. Depress the desired time key. f. Record the data from density data displays. 1-23. DETERMINE DENSITY AND MOISTURE FROM CALIBRATION CHARTS 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 answers. 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. RATIOS DENSITIES 0 246 127.00 0.243 127.50 0.240 128.00 0.238 128.50 0.235 129.00 0.232 129.50 Figure 1-8. NOTE 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. 1-17