The concrete quality depends on setting and curing. In its most basic form, concrete maturity requires the collection of time and temperature data. As construction practices affect the ultimate outcome, such historical data is useful and often demanded by Structural Engineers and Owner Representatives alike.
Although the technology for measuring concrete temperature has been in existence for some time (e.g. thermocouples) new technology is now available to make this process of monitoring of concrete temperatures a lot easier.

Sigma is now making available a new development in loggers, which allows you to measure, monitor and record the temperature as well as the concrete deformation, starting from the first hours of the setting and following through to the following years, without anyone being able to tamper with the logger.

The logger has 2 versions with Integrated sensors :
one version for temperature only
and one version with temperature and deformation gauge.

Technical Characteristics
Operating temperature: -20°C ... +80°C
Temperature accuracy: ± 0.3 °C
Deformation range of measure: -1850 ppm to +1850 ppm for a bridge excitation of 2.7 Volt
Deformation Accuracy: +/- 0.56 ppm in voltage
IP rating: IP68
Resistant to dust, to liquid concrete, suitable for continuous immersion in water under static pressure of 6 bar.
Casing: tear-proof, crushing proof and unbreakable
Autonomy: 5 to 10 years (depending on measure frequency and operating temperature)
Memory Capacity: 32 256 measures with date and time
Measurement Frequency: Can be set from 10 minutes to 4 hours
Dimensions: Casing: 132 x 75 x 70 mm
Weight with battery: 300g
5 meters antenna cable, compliant with installation in deep foundations
Sensors calibrated at the factory
Software with database to store and sort the measurements

Functionality
The logger is buried directly (antenna included) into the concrete and records the corresponding measurements in its embedded memory. When desirable the user can download over the air all the measurements. With the long range antenna, the radio remains operational even under foundations or major works.

As all the measurements are dated, the user gets the complete history of the supervised concrete.