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 80 m 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 200 m at Ciqikou station by analyzing the subsidence rate profile perpendicular to subway line No. 7 and that the maximum land subsidence rate is 23.2 mm yr −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.

Analysis of the Contribution Rate of the Influencing Factors to Land Subsidence in the Eastern Beijing Plain, China Based on Extremely Randomized Trees (ERT) Method

“…The additional stress information engendered from static and dynamic loads in the LDD land subsidence funnel was obtained by using the method outlined in Section 3.2. This additional stress will not cause significant land subsidence in this stratum when the additional stress is less than 20% of the stress engendered from the gravity of the soil above the depth [28]. Table 4 shows the detailed parameters of the soil in the LDD land subsidence funnel, while Figure 8 shows that the maximum value of the additional stress engendered from the static and dynamic loads is less than 20% of the stress engendered from the gravity of the soil when the depth is greater than 65.1 m by assuming that the density of the soil above this depth is 1930 kg/m 3 .…”

The effect of CRD method and auxiliary construction on surface settlement in shallow-buried tunnels

“…The deformation of existing tunnels caused by shield underpassing is dominated by vertical settlement accompanied by torsional deformation; these existing tunnels experience the maximum settlement and torsional deformation in the crossover area. The impact area of ground settlement caused by the metro construction is 200 m, and the maximum ground settlement rate is 23.2 mm yr -1 (Li et al, 2020). Installing grouting rings on existing tunnels can effectively reduce the amount of tunnel settlement, and increasing the length and thickness of grouting rings can protect existing tunnels (Qi et al, 2021).…”