Unique digital crack meter monitors cracks in buildings, bridges, levees and tunnels

Unique digital crack meter monitors cracks in buildings, bridges, levees and tunnels

Within 5Groningen, an initiative of Economic Board Groningen, a digital crack meter has been developed that measures in three directions using sensors and 5G. It is the world's first digital crack meter that accurately captures both the width, length and depth of the crack.

The crack meter can be attached to all kinds of structures: buildings, bridges, dikes or tunnels. 'One of the advantages of this product is that you don't have to travel to the site each time to read the measurement data,' said initiator Arjen Miedema of StabiAlert. Using 5G, the crack meter is always online for a short time to send data. That way, the crack sensor's small battery lasts a long time. 'The crack meter sends a signal every hour, so you can monitor the development of a crack over a number of years. And that saves a lot of time, money and CO2.' Together with Vodafone, Hanzehogeschool Groningen and the University of Groningen, Arjen Miedema and Wessel Koning of Interay Solutions successfully conducted a 5G pilot at 5Groningen. And now it's time for the next step: to the market!

View the website of StabiAlert View the Interay Solutions website

Earthquakes and cracks in buildings

Arjen Miedema is owner of StabiAlert in Bedum, developer of vibration and tilt meters. 'Here in the earthquake area you see a lot of subsidence and damage to buildings. I saw engineers sticking strain gauges on cracks and watching the development of the crack every other week,' says Miedema. 'That can be done better and more efficiently, I thought.'

"NOM portfolio company StabiAlert is constantly on the move. Now with the crack meter. A wonderful addition to StabiAlert's product palette. They measure vibrations, tilt and cracks. AND all this real time and remotely."
Chantal Leijendekker, Investment Manager NOM

Monitor safety of buildings, bridges and tunnels

Miedema developed the crack meter together with Wessel Koning of Interay Solutions, a specialist in sensor technology. 'In this crack meter we have placed a number of magnetic sensors next to each other, with a magnet above them,' Koning explains. 'Using algorithms, we can measure three vectors/directions and thus monitor the crack. These directions correspond to the movement of the crack in the wall. If a tunnel consists of 25 segments, you can hang 25 crack sensors, for example. Together, the crack sensors image the entire tunnel and show how the segments move relative to each other.' The crack sensor helps to monitor the safety of a bridge or tunnel. As soon as the measurement data show that a crack is growing rapidly, timely action can be taken.

Energy efficient thanks to 5G

With 5G, it is possible to be online for a short moment and send data. This saves a lot of energy, making the small battery in the tear meter last as long as about 5 years. Thanks to the features of 5G, the tear meter is smaller, more accurate and cheaper to use than existing tear meters. Potential users of the crack meter include engineering firms, governments, semi-governments, asset managers and managers of buildings, bridges or tunnels. The crack meter is going to save a lot of time and money, according to Miedema and Koning. It is no longer necessary to regularly travel to the crack meter, turn off a road or stop a track.


At 5Groningen, Miedema and Koning gained access to funding and were supported in the grant application process. They also came into contact with Vodafone, Hanzehogeschool Groningen and the University of Groningen. Vodafone brought expertise on how 5G works and provided chips for the crack meter: a kind of SIM card, but small in chip form.

University of Groningen has set up a server to run communications via 5G. Students from Hanze University of Applied Sciences Groningen have been researching opportunities in the German market. In addition, a number of students have been working on a web application for the crack sensor. Another group of students is investigating how to market the product and is working on a proposal for the design and branding.

After extensive testing in 5Groningen's 5G lab, the first field tests have begun. Miedema and Koning attached crack gauges to two metal buildings standing against each other. Temperature differences cause the metal to move, which brings the crack meter into focus after just a few days. A crack meter was also placed on a crack in an industrial building. The first results are good: the crack meter measures to the 10th millimeter. After the summer, Miedema and Koning want to enter the market with their crack meter.