Application of Synthetic Aperture Radar Interferometry to monitor surface deformations of the Trans-European Transport Network (TEN-T) – A case study of the motorways crossing areas of mining operations in the Upper Silesian Coal Basin, Poland

Abstract

Underground hard coal mining causes surface deformations. When the mining operations are conducted beneath linear objects, such as motorways, there is a risk of deformations of the axis of the road and its horizontal and vertical alignment (additional bends and vertical curvatures, longitudinal inclinations, deformations of cross-sections). In the areas subjected to mining operations, mining plants conduct geodetic monitoring. Due to their labour intensity and costs, geodetic measurements are usually made only a few times a year. The article discusses the possibility of applying Interferometric Synthetic Aperture Radar (InSAR) to monitor the subsidence of the vertical alignment of motorways caused by mining operations and its advantages and disadvantages compared to the currently used methods of geodetic measurements. The tests were conducted in two sections of motorways within the Upper Silesian Coal Basin (Poland) in the areas of intensive hard coal mining operations. Radar imaging of the surface made by the European Space Agency's (ESA) satellite Sentinel-1 equipped with the Synthetic Aperture Radar (SAR) was used.