The TORRENT Permeability Tester is a measuring instrument which is suitable for the determination of the air permeability of cover concrete by a non-destructive method.
It operates under vacuum and can be used at the building site and also in the laboratory.
The essenfial features of the TORRENT method of measure- ment are a two-chamber vacuum cell and a pressure regula- tor which ensures an air flow at right angles to the surface and into the inner chamber. This permits the calculation of the permeability coefficient kT on the basis of a theoretical model.
In the case of dry concrete, the results are in good agreement with laboratory methods. such as oxygen permeability, capil- lary suction, chloride penetration and others. The quality class of the cover concrete is deteimined from kT using a table.
The humidity, a main influence on the permeability, is com- pensated by additionally measuring the electrical resistance p of the concrete. With kT and p, the quality class is obtained from a nomogfain.
The list shows the values of the constants which are used in the calculation of kT and L. They cannot be changed.
Underneath there is the code of the resistance probe WENNER-PROCEQ. The setting must be identical with code on probe. Change according to information at bottom of display.
Technical Data
Display Unit:
- Nonvolatile memory for up to 200 measured objects.
- Display on 128 x 128 graphic LCD.
- RS 232 C interface.
Integrated software for printout of measured objects and transmission to PC.
- Operation with 6 batteries LR6 1,5 V for about 60 h or commercial power unit 9 VDC/0.2 A.
- Temperature range -10° to +60°C.
Carrying case 320/285/105 mm, total weight 2.1 kg.
Control unit and vacuum cell:
- The volume of inner chamber and hose and the cross- sectional area of the inner chamber are terms in the for- mula for calculating kT and L, They must therefore not be changed.
- Vacuum connection: small flange 16 KP,
- Carrying case 520/370/125 ruin, total weight 6.3 kg.
Resistance probe WENNER-PROCEQ:
Electrode spacing 50 mm
Vacuum pump:
The instrument is operated with a commercial vacuum pump. Technical Data according to DIN 28 400:
Suction capacity 1.5 m'fh
Final total pressure approx. 10 mbar
Suction-side connection Small flange 10 KF/l6 KF High water vapour toleration
Regarding operation and maintenance of the pump, please con- sult the relevant instructions.