Sensors & Software PDP1000, User Manual

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PDP User's Guide PDP Collection Software
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• Density – Site Specific – measurements of the asphalt properties at the
survey site are used to create a unique, site-specific means of translating
relative permittivity to density. When the information is available, other
parameters such as relative density can be displayed in addition to the
absolute density of the asphalt, expressed in units of g/cm
3 . This is a far
more complex calculation that relies on inputting the A, B & C coefficients of
the parametric relationship as well as the Maximum Density. A, B, C and
Maximum Density values can be obtained from a core sample using the PDP
Toolkit PC Software. While more complex, this is a more accurate
representation of the true density.
NOTE: Selecting this option requires A, B & C coefficients and Maximum
Density values filled in under the Parameters tab, otherwise an error will
result
• Relative Density – sometimes called normalized density or percentage
compaction, this parameter expresses the density measured as a percentage
of the site-specific maximum density. To calculate the relative density, the
max density must be set under Plot Options. This is usually obtained from a
core sample via a testing lab. Note: relative density = (1
– Air Void
Content).
NOTE: Selecting this option requires site specific A, B & C coefficients and
maximum density values filled in under the Parameters tab, otherwise an
error will result
• Air Void Content – expressed as a percentage of how much of the volume
of the asphalt is air. This requires the Max Density value to be set under Plot
Options. Note: Air Void Content = (1
– Relative Density).
NOTE: Selecting this option requires site specific A, B & C coefficients and
Maximum Density values filled in under the Parameters tab, otherwise an
error will result