29
© 2017 Proceq SA
Figure 30:
Multiple reinforcement layers
In overlapping areas the measured diameter will be generally 1,4 times
higher than the actual single rebar size (see Figure 31).
D
s
~
1.4 D
r
C
Ds Ds= Set Diameter
Real Diameter D
r
Figure 31:
Apparent diameter on overlapping rebars
In any of the two cases mentioned above, or more generally whenever
the requirements of the minimum spacings are not met,
the diameter
to be set in order to have correct cover readings is the one that is
measured by the Profometer 6, regardless of the actual rebar size
(apparent diameter).
Rebar Orientation
The strongest signal results when the Center Line (CL) of the probe is
parallel to a bar. The CL E of the Profometer 6 probe is the longitudinal
axis of the probe. This property is used to help determine the orientation
of the rebars by rotating the probe slowly and searching for the maximum
signal.
Welded Meshes
The instrument cannot detect whether the rebars are welded to one an-
other or connected with binding wires. The two reinforcement types with
the same dimensions however create different signals.
The setting of the bar diameter must be slightly higher than the actual
diameter of the mesh rebar. The input depends on the bar diameter and
on the mesh width. This input value should be determined by means of a
test measurement on an open system with specific rebar mesh wire ar-
rangements. Measure on each arrangement with different covers to find
out the diameter setting at which the correct cover is indicated.
Welded reinforing mesh
a
1
[mm]
a
2
[mm]
current d
[mm]
d to be set
[mm]
100
150
100
150
5
6
8
7
Figure 32:
Examples for diameter settings at welded meshes to measure
correct cover values
NOTE! The “Standard Range” must be selected. With the
“Large Range” or “Spot Range” selected, locating of the
rebars may be completely wrong.
