Sensors & Software PDP1000, Руководство пользователя

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PDP User's Guide Methodology
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1. Determine simple pavement variability using permittivity (K) data.
2. Determine pavement density variability using permittivity (K) transformed to
density.
3. Determine site specific pavement density where permittivity (K) is
transformed to ‘true’ density using field cores to obtain a conversion
relationship.
Each method is explained below:
5.3.1 Dielectric Permittivity (K) for uniformity
Knowing that K is directly related to density, determining the variability of K over
an area provides the same information as the variability of density over that area.
Since K values can be determined at cm intervals, the detail on variability can be
mapped at a far higher spatial resolution than could ever be attained for coring
density determinations.
Statistics on the variation of K will be very similar to the statistics of density. The
location of extreme high and low K values will indicate the location of areas of high
and low density. Such areas can then be targeted for coring. If the extremes are
acceptable then all areas between can be assumed to be acceptable.
Start by traversing a line or run multiples lines to cover an area. Display K vs.
position on the plot (Figure 5-1).