The challenge of measuring the moisture content of concrete has been a much-titled topic lately. No wireless devices have been available for monitoring that would reliably measure the drying process. In addition to reliability, the usability of the control system in varying site conditions has also been found to be problematic. Thus, the issues to be addressed were the usability and reliability of the sensor, the collection and transmission of data in a sensible way, and the presentation of the data in an easy-to-handle format.
The challenge for construction sites was taken up by eGate, which wanted to solve indoor air problems from the root level. The Smart Building Innovation concept aims to develop condition monitoring of buildings during the construction phase and throughout the whole life cycle. The concept supports the development of construction quality and the improvement of cost efficiency.
“eGate collects reliable data starting from the construction phase, and the data can be used to analyse it, among other things, to develop different forecasting models.”
eGate’s goal of monitoring concrete castings of floors was achieved by Nokeval using wireless transmitters and a new type of sensor technology. Our experts found a suitable sensor that can meet the demands of very challenging humidity measurements. The new resistive humidity sensor we import into Finland does not get tired like the traditional capacitive sensor, and in addition it is really fast and has been found to be at least as accurate as the standard measurement method. Thanks to the sensor, it is possible to measure changes in humidity in real time on construction sites without delays that consume expensive working time.
An approved sensor was connected to wireless transmitters utilising LoRa modulation. Thanks to LoRa, the coverage of an individual device is in the order of kilometres instead of tens of meters. The devices send the data directly via the base station to the eGate service, from which the measurement results can be monitored both as an updated view and as historical reports. The measurement data is stored in the system so that it is easy to return to events during construction, even in the later stages of the building’s life cycle. Alarms can also be defined in the system to inform the necessary persons if necessary. With the help of monitoring, the necessary measures can be taken in time, which contributes to the timely completion of the project and thus significant cost savings.
The eGate service is already in use by all of Finland’s largest players in the construction industry, and by the summer of 2018, the feedback received from developers, builders and other actors providing condition management services has been very positive. A system implemented with similar devices is not available from other service providers.