Subsidence monitoring with TerraSAR-X data in Beijing Central Business District and subway tunnelings, China

Abstract

Land subsidence caused by large-scale engineering construction may damage the surrounding infrastructures and cause huge economic losses in inner-city environments. In this study, we used PS-InSAR technology on 68 TerraSAR-X images to acquire deformation in the Beijing Plain between February 2010 and December 2018. Then, we calculated the additional stress derived from building loads using the method proposed by Boussinesq in the Central Business District (CBD). We found that the depth of influence of additional stresses induced by building loads was 80m and that spatial distribution pattern of the land subsidence rate agreed well with the additional stress. We found that the influence range of ground subsidence caused by metro construction is 200m at Ciqikou station by analyzing the subsidence rate profile perpendicular to subway line No. 7 and that the maximum land subsidence rate is 23.2mmyr-1. Time series analysis of PS around Ciqikou station shows that land subsidence caused by excavation activities mainly occurs in the period of metro construction. Ground deformation rate decreases gradually after 372 d of subway operation. The results of both cases show that large-scale engineering construction will lead to significant land subsidence which should be considered in future urbanization.