Chemical Additives
21
Adjusting and Measuring
SONO WZ
Translation of the Original Instructions for Use
SONO WZ measures the free water in the
fresh concrete, as well as some of the
core and suction water. There are types of
rock that absorb very little core water, but
also strong absorbing types of rock, e.g.
sandstone or lime grit, which can absorb
up to 50 l of core water.
The core or suction water is not used for
cement bonding and is, therefore, not tak-
en into consideration for the w/c ratio.
SONO WZ measures three types of
water
In principle, the SONO WZ measures the
same amounts of water as the Darr method.
1. The free water in the concrete mix,
which is taken into account for the water/
cement ratio. This water is the actual
target value you are looking for when
using the SONO WZ.
2. Some of the core water, water that is
absorbed by the aggregates, whereby
only a part (approx. 1/3) of the core
water can be measured here by the
SONO-WZ. Depending on the type of
rock, the core water can amount to
10 to 35 l/m³. This (correction) value is
represented in the G-Set parameter
(approx. 2/3 of the core water) depend-
ing on the concrete formulation and
rock type. Typically, the G-Set value is
approx. -10 l/m³, assuming a core water
content of 15 l/m³. This -10 l/m³ is then
automatically subtracted during meas-
urement with the SONO WZ so that
the display in the hand-held measuring
instrument matches the effective water
content. (Fig. 3)
3. Additives that behave like water are,
therefore, also measured by the SONO
WZ This should be taken into account
accordingly. (Fig. 4)
Fig. 4
Fig. 3
General G-Set Parameters
