EVALUATION OF BUILDING STABILITY IN SEOUL, KOREA, USING PSINSAR ALGORITHM

摘要

This paper presents an effect and correction of the thermal expansion of buildings when to measure deformation in urban area by the Persistent Scatterer Interferometry (PSI). For precise deformation measurement of buildings in a city, the thermal expansion should be considered as a component of Persistent Scatterer Interforometric phase. In order to extract and compensate the phase component of the thermal expansion, we propose a modified PSI algorithm. This study is then to evaluate overall stability of the buildings in Seoul, Korea, using high-resolution TerraSAR-X SAR data., The core ideas are to optimize a thermal expansion factor using air temperature data and to model a corresponding phase by filing the residual phase. To show the effectiveness of the proposed method, we carried out a X-band PSI analysis using TerraSAR-X SAR data acquired for two years from November 2011 to September 2013. Precise deformation histories were retrieved after removing the thermal expansion phase. Several examples showing subtle motion of individual building are presented. Some of the detected moving points well coincide with pre-reported subsidence sites and sinkholes.