Working area
The microwave borehole method was fully developed at BAM. This method enables depth resolved moisture determination in brickwork. For the measurements, two parallel holes with a diameter of 12 mm each and a distance of about 5 cm have to be drilled. The depth of the holes depends on the thickness of the masonry wall to be investigated.
Depth resolved moisture measurements in brickwork with the microwave borehole method
At present, depths of up to 2 m are possible. In these boreholes, two dipole antennas connected to semi ridged high frequency cables can be moved stepwise. The moisture determination is based in the measurement of the absorption of the microwave energy in the material between. Using calibration curves allow the user to calculate the moisture content from the absorption coefficient. This method can be applied repetitively, thus it is possible to observe the moisture condition for longer periods, e. g. for monitoring the dry up process of the wall after removing the cause of moisture damages. The method as well as the dipole antennas are patented.
At time this method is effectively applied to moisture determination in brickwork. For the future, it is planned to optimise the technique for applications in concrete structures.
Service
Division VIII.2
Dr. rer. nat.