Potentials and limitations of using radar satellites for the monitoring of transport infrastructure assets

Interferometric Synthetic Aperture Radar (InSAR) satellites represent a unique technology to monitor the deformations of civil engineering structures remotely. Over the past decade the Austrian Institute of Technology has applied this innovative method to an ever-increasing variety of infrastructure components, such as bridges, motorways, railways and flood protection systems. We also gained experience with different types of satellite data, ranging from freely available preprocessed data provided by the European Ground Motion Service to commercially available high-resolution X-band systems. In this contribution we wish to share our main insights and highlight the potentials, but also the limitations of the InSAR technology in this field of application. We describe the most promising use cases from our perspective and provide some recommendations for the choice of data source for the respective applications. Furthermore, we address the difficulties which may arise for certain types of infrastructure assets or circumstances and suggest some approaches to overcome them. Finally, we shed light on some of the unique features of InSAR monitoring, such as the possibility for retrospective analysis, which set it apart from conventional structural health monitoring techniques. We conclude with an outlook on how future satellite missions may extend the range of possibilities.