Alireza Malehmir awarded 2024 Innovation Prize ‘Hjärnäpplet’

“I see it as a reward to our research team. People have put time and energy into this. They have been involved from when it was a mere concept to a product that is now globally recognised and has been used in many places, helping to solve societal problems,” says Malehmir, Professor at the Department of Earth Sciences.

The innovation he created is a seismic landsteamer system, based on the fact that seismic waves travel at different levels of efficiency and speed, depending on the material they encounter. This is what makes them useful for analysing what is under the ground and how stable it is.

“It all started when we realised there were a lot of infrastructure projects going on in Sweden. This was in 2010–2011 when the Stockholm Bypass road and tunnel system was announced. We knew it would be very challenging, given the previous problems with tunnelling through Hallandsåsen,” explains Malehmir.

Careful assessment of the ground conditions was therefore necessary. Traditional seismic methods involve embedding sensors in the ground, which is time-consuming and does not work well in urban environments. For example, urban noise can interfere with measurements.

GPS time-coordinated

Malehmir wanted to find a way round all these problems. He envisioned a mobile solution that could map larger areas relatively quickly, so he designed a landstreamer consisting of interconnected digital sensors attached to sledges. The sensors detect seismic waves created by something being pounded hard into the ground. The entire process is time-coordinated using GPS.

Companies in the infrastructure sector began to take an interest in the development work early on, and in 2013 the research group was able to present its first prototype. They were able to test it almost immediately in real life during the construction of the Stockholm Bypass when the first tunnel was being excavated.

“We were not sure how it would work. We went there at night so that traffic would not be a problem. And even though we only used 20 sensors, the results were surprisingly good and everyone was happy,” Malehmir recalls.

The successful results led to his team being invited to use the equipment in the construction of the double-track Varberg tunnel. This also produced a good picture of the ground conditions. Since then, enquiries have come from all over the world.

“We have learnt a lot. In the beginning, we couldn’t map more than 400 metres a day or something like that, but last year in Denmark we managed three kilometres a day. That is a huge improvement,” continues Malehmir.

Mapping faults in Seoul

One of the biggest assignments so far was in South Korea, where cracks and faults under major cities, including Seoul, were mapped to assess earthquake risk.

“This is vital work. When the Fukushima earthquake happened, they were scared, because in South Korea the big cities still have old houses. If something similar were to happen in the South Korean hinterland, they need to be better prepared,” Malehmir notes.

He started the company Nordic Geophysics in 2018. Three landstreamers have been produced to date, one of which has been sold to Denmark. There is also interest from South Africa in buying the landstreamer.

Nordic Geophysics has already patented the next-generation landstreamer, which is now on the drawing board. It will be powered by batteries instead of electric cables and will therefore be more flexible. A contract has recently been signed with a manufacturer.

Åsa Malmberg