Troxler 4640-B, Operation And Instruction Manual

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SITE PREPARATION/GAUGE POSITIONING
The 4640-B Thin Layer Density Gauge is designed for use on
asphalt surfaces and does not require a great deal of site preparation.
NOTE
Keep the gauge turned parallel to the direction of the
paver and rollers (see Figure 3–4).
♦ Remove any loose material (sand, aggregate, and so on) from
the test site.
♦ Ensure that the gauge does not “rock;” it must remain level and
steady. If rocking occurs, find a more suitable test site. To take a
measurement around a core, the operator may move the gauge a
few inches away from the core to level the gauge.
Figure 3–4 shows the gauge positioned
around a core site. This type
of measurement is taken after the core has been cut. When taking
this type of measurement, Troxler recommends averaging four 1-
minute counts taken around the core site.
Figure 3–5 shows the gauge positioned
over a core site. This type of
measurement is taken before the core is removed.
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