Tunneling-induced Ground Subsidence Revealed by Spaceborne and UAV-borne Synthetic Aperture Radar Interferometry: A Case Study in Shenzhen, China

Abstract. During the construction of subway lines, the excavation process of tunneling can sometimes cause safety hazards such as ground subsidence and cracks in surrounding buildings and roads along the excavation line. Therefore, monitoring the ground deformation along the tunneling lines is crucial to ensuring the safety of the surrounding infrastructures. Driven by the rapid advancement of unmanned aerial vehicle (UAV) technology, UAVs as remote sensing platforms equipped with miniature synthetic aperture radar have become an effective solution for studying ground subsidence associated with construction. Compared with traditional methods, UAV-based remote sensing platforms have significant advantages such as flexible deployment, high resolution, and short revisit time. This study used a UAV as the remote sensing platform with a miniSAR for data acquisition and applied the differential synthetic aperture radar interferometry (DInSAR) method to monitor surface deformation in the area along Longcheng avenue, Longgang district, Shenzhen, China. Results show that deformation in the anomalous area ranges from −2.67 cm to 1.05 cm. Finally, cross-validation was performed using results from persistent scatterers interferometry (PSI). Deformation analysis results for part of the tunneling route on Longcheng Avenue in Longgang District, Shenzhen, China, demonstrated that the UAV-SAR method can effectively monitor deformation associated with underground constructions, i.e., tunneling and grouting.