4–22
S
S
i
i
t
t
e
e
P
P
r
r
e
e
p
p
a
a
r
r
a
a
t
t
i
i
o
o
n
n
Preparation of the test site surface is critical to gauge
performance. This section provides site preparation procedures
for both soils and base courses and asphalt surfaces. To ensure
the most accurate gauge readings, the appropriate preparation
procedure should be followed.
Soil and Base Course Preparation
Locate a level site free from any large holes, cracks, or debris
(soil surface conditions are critical to accurate
measurements).
Smooth the surface by moving the scraper plate in a back
and forth motion. Filler such as fine sand may be used to fill
in the surface voids.
CAUTION
Use only enough filler to fill the voids. Too much filler
will cause an error in the measurement.
For direct transmission measurements, put the drill rod
through the extraction tool and then through one of the
guides on the plate (see Figure 10).
WARNING!
Under no circumstances should you use the source
rod of the gauge to drill holes.
Wearing a radiation badge and safety glasses (or other
locally approved safety devices), step on the plate and
hammer the drill rod at least 50 mm (2 in.) deeper than the
desired test depth. The drill rod increments include the
additional depth.
To Next Page
Loading...
Need help?
General
