Sensors & Software PDP1000, User Manual

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PDP User's Guide PDP Collection Software
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• Density Offset – used when calculating Density. This applies a shift in the
data. A user would input a density offset value to bring the PDP surveyed
measurements in line with that from a core sample or possibly calibrated
nuclear gauge measurement.
• Density - Site Specific - A , B & C coefficients, as well as Maximum
Density are used in a polynomial equation that accurately transform
permittivity to density (this is explained in Appendix G:). Once cores are
obtained, these coefficients can be calculated from the PDP Toolkit software.
The coefficients can be input here so subsequent PDP measurements will be
accurate. The more accurate the information obtained, the more accurate
the future PDP measurements for that section of road.
The above 4 values are required before data can be plotted showing Density-
Site Specific, Relative Density and Air Void Content.
The details on measuring maximum density are part of AASHTO Designation
PP 98-xx, where xx is the revision number.
Data Range : Controls the display of data on the vertical axis on the main display.
If set to Auto , the labels on the vertical axis will display the full range of data. If
set to Manual , the user can set the min and max values accordingly.