Preparations for solid concrete – Vaisala SHM40 User Manual
Page 23
Chapter 3 ____________________________________________ Humidity Measurement in Concrete
VAISALA _______________________________________________________________________ 21
Preparations for Solid Concrete
Prepare the boreholes at least three (3) days before the measurements, so
that the humidity inside the plastic tube has time to reach equilibrium
with the humidity in the concrete. Each borehole must be completely
prepared and sealed during stabilization, ideally with the probe remaining
inside the tube. Follow the instructions below.
1.
Three days before the measurements, drill at least two holes with
diameter of
16 mm and appropriate depth. See section
2.
Clean the hole thoroughly using a vacuum cleaner.
3.
Press a plastic tube (19266HM) into the hole. If you need
something to press it with, use the lid of the protective cover. See
Figure 5 below.
1111-095
Figure 5
Pressing the Tube into the Hole
4.
Now you have a clean borehole that reaches to the correct depth,
and a plastic tube in it. For best results, you can also seal the crack
around the tube and concrete with a suitable material.
Continue from section Inserting the Probe and Sealing the Hole on
page 24.