TanDEM-X satellite mission,
image courtesy of Astrium
Astrium has signed a contract with Hong Kong’s Spatial Technology Limited to provide precise surface movement monitoring information for the construction of a 3.5km tunnel on Hong Kong Island. The tunnel forms part of the Wan Chai Bypass Project, a 4.5km section of highway running along the northern part of Hong Kong Island that will improve transport links in the region and reduce traffic congestion.
The GEO-Information Services division of Astrium Services will use data from the Astrium-built TerraSAR-X and TanDEM-X radar satellites to provide surface movement information before and during the tunnelling process. This data is essential in order to ensure that the risks of tunnelling are reduced in what is a highly populated area, enabling project teams to understand the impact of the underground construction work on the site’s surface, surrounding buildings and infrastructure. Using a radar interferometric approach which combines several Synthetic Aperture Radar (SAR) datasets from those satellites, surface motion information will be provided that offers an accuracy within a few millimetres, keeping project teams continually informed of surface subsidence and/or uplift resulting from the underground construction work. This will cover the tunnel area as well as the wider construction site, a major advantage compared to terrestrial monitoring.
