Page - 809 - in Book of Full Papers - Symposium Hydro Engineering

Satellite SAR (Synthetic Aperture Radar) is one of remote sensing technologies which makes it possible to measure distributions of ground surface deformations over a wide area, and it has been commonly used to evaluate crustal displacement due to earthquakes and volcanic activity, as well as landslides. Recently, researches on external deformation measurements for dams using satellite SAR data have been conducted [1] to [8]. For the purpose of technological development to contribute to the rationalization and efficiency of dam deformation measurements, the authors have already shown the external deformations of five rockfill dams using satellite SAR data [6]. The authors have found that the satellite SAR produced external deformation measurements which were with an accuracy of about 5 mm when compared with the external deformation measurements obtained by GPS or electro-optical survey. This paper reports on the results of external deformation monitoring of nineteen rockfill dams in Japan using satellite SAR data. The external deformation of dams for about two years by satellite SAR was measured and compared with other existing geodetic measurements such as GPS or electro- optical survey. 2. EXTERNAL DEFORMATION MONITORING OF NINETEEN ROCKFILL DAMS USING SATELLITE SAR DATA 2.1. OUTLINE OF NINETEEN ROCKFILL DAMS AND SATELLITE SAR DATA FOR STUDY Fig. 1 shows the locations of the dams for study. Table 1 shows main specifications of nineteen rockfill dams and observational data of satellite SAR for study. In Table 1, ASC and DSC mean ascending and descending orbits of satellite SAR shown in Fig. 2, respectively. A total of 135 scenes of SAR data was used. Fig. 1 Locations of Nineteen Dams for Study A B C D E FG H IJ K L M N O P QR S 809