A new satellite system will help to identify bridges that could collapse. Researchers at the Jet Propulsion Laboratory (JPL) of NASA and the University of Bath have in fact developed a new pre-alarm system that uses satellite images to identify even the smallest deformations or small movements in bridge structures in order to identify the risk of collapse.
The idea came when scientists verified 15 years of satellite images of the Morandi Bridge in Genoa, of which a large section collapsed in August last year causing the death of 43 people. In the study, published in Remote Sensing, it is shown how the bridge, in these satellite images, already showed signs of deformation in the months that preceded the collapse. The system, in fact, is able to intercept the deformations of the structures with a millimetric precision.
“We have shown that it is possible to use this tool, in particular the combination of different data from satellites, with a mathematical model, to detect the first signs of collapse or deformation,” says Giorgia Giardina, a researcher at the University of Bath and one of the authors of the study.
The system would be better able to detect signs of deformation or structural movement in bridges, but also in other buildings or structures, compared to today’s monitoring systems that substantially detect these modifications only at specific points, ie those in which they are positioned sensors.
Instead, this new technique involves an almost real-time monitoring of the entire structure with unprecedented frequency and accuracy, as also emphasized by Pietro Milillo, researcher of the JPL and another author of the study. Combining this technique with other more “classic” techniques, the potential for bridge collapse prevention activities would become even higher.
This is a system whose conception has been made possible thanks to the major advances in satellite technology that have taken place in recent years.
In this case, the researchers combined the radar satellites of the COSMO-SkyMed constellation of the Italian Space Agency (ASI) and the Sentinel-1a and 1b satellites of the European Space Agency (ESA).
Thanks to the radar data of these satellites, it is possible to construct a very detailed and specific 3D image of a bridge or any building on the earth’s surface.