GROUND SUBSIDENCE ALONG SHANGHAI METRO LINE 6 BY PS-InSAR METHOD

Abstract

ABSTRACT:With the rapid development of urban economy, convenient, safe, and efficient urban rail transit has become the preferred method for people to travel. In order to ensure the safety and sustainable development of urban rail transit, the PS-InSAR technology with millimeter deformation measurement accuracy has been widely applied to monitor the deformation of urban rail transit. In this paper, 32 scenes of COSMO-SkyMed descending images and 23 scenes of Envisat ASAR images covering the Shanghai Metro Line 6 acquired from 2008 to 2010 are used to estimate the average deformation rate along line-of-sight (LOS) direction by PS-InSAR method. The experimental results show that there are two main subsidence areas along the Shanghai Metro Line 6, which are located between Wuzhou Avenue Station to Wulian Road Station and West Gaoke Road Station to Gaoqing Road Station. Between Wuzhou Avenue Station and Wulian Road Station, the maximum displacement rate in the vertical direction of COSMO-SkyMed images is -9.92 mm/year, and the maximum displacement rate in the vertical direction of Envisat ASAR images is -8.53 mm/year. From the West Gaoke Road Station to the Gaoqing Road Station, the maximum displacement rate in the vertical direction of COSMO-SkyMed images is -15.53 mm/year, and the maximum displacement rate in the vertical direction of Envisat ASAR images is -17.9 mm/year. The results show that the ground deformation rates obtained by two SAR platforms with different wavelengths, different sensors and different incident angles have good consistence with each other, and also that of spirit leveling.

Hazards threatening underground transport systems

“…Geological hazards are within the typologies of hazards that may threaten metro systems. Much of the available literature (Dashko 2016;Wu et al 2018c) deals with planning and construction phases since metro stations settlements during excavations are highly subject to geotechnical problems and the influence of the water table (Raben-Levetzau et al 2004). As this literature review disregards the metro systems development phase hazards, these research types are not addressing here.…”

“…Assessment of the normal stress, shearing stress, or any deformation kind of the section of a Metro underground line (Huang et al 2014;Shi et al 2018) b. Effects of metro-induced ground-borne vibration (Wu and Xing 2018) c. Investigation of the train-induced settlement of a metro tunnel in clays or permeable strata (Di et al 2016;Huang et al 2017a;Tang et al 2017) d. Seismic response of a segmented metro tunnel with flexible joints passing through active ground fissures (Liu et al 2017) e. Geotechnical conditions of deep running metro tunnels (Dashko 2016;Wu et al 2018c) f. Failure of metro tunnels that pass obliquely through ground fissures at low angles (Peng et al 2016) g. Countermeasures to mitigate the adverse impact caused by the activity of ground fissure (Wang et al 2016) Geohazard: Groundwater flows 6 Papers a. A method used to predict time-dependent groundwater inflow into a metro tunnel (Liu et al 2018) b.…”