ABSTRACT
InSAR technologies are becoming increasingly important in all phases of civil engineering projects. The high-resolution TerraSAR-X (TSX) data presented here demonstrate the unique advantages of using SqueeSARTM to monitor excavation-related ground deformation. The data reveal settlement troughs caused by Crossrail tunnels along their entire length. The settlement patterns are shown to be heterogeneous, both in extent and time. Ground-based monitoring data allow us to validate the remotely sensed measurements at Bond Street Station and the Limmo Peninsula. We also detect active dewatering, which has caused ground deformation over an area of several km². The TSX data show both ground settlement and the subsequent ground rebound caused by the different stages of dewatering. SqueeSARTM is used for historical ground deformation analysis and for ongoing monitoring. In general, InSAR is complementary to conventional ground-based measurement systems, and is the only way to create regional ground surface deformation maps with millimetre-scale accuracy.
