Simulation Of Ground Subsidence Based On PS-InSAR Monitoring Deformation Field Constraints

Since 2002,Beijing has established five city emergency water source site.As of high strength and large-scale exploitation of groundwater for emergency water source sites,groundwater level dropped sharply.As a result,it induced the subsidence.Land subsidence has damaged to buildings and underground water pipeline of Beijing,which brings threat to the development and construction of the city.Therefore,establishing precaution system of land subsidence prediction is imminent.Land subsidence numerical simulation is the core of land subsidence early warning forecast system,therefore,to establish the emergency water source land subsidence numerical model has practical significance.The subsidence model used this time fully considers the lagging of water released from weak permeable layers.It can simulate time-dependent drainage and compaction of thick interbeds.This paper see the Shunyi and the south of Huairou and Miyun district as the research area.Based on the collected 154 borehole data,the analyze of the distribution features of aquifer and weak permeable layer in the study area is made.Based on meteorological date and production of wells and the underground water level data,the groundwater flow numerical model in 2003-2007 is established.The surface deformation information obtained by the use of PS-InSAR technique can constraint the land subsidence model by repeatedly adjusting parameters(inelastic skeletal specific storage).The divisions of skeletal specific storage can be obtained.Contrast subsidence monitoring data of Tian zhu subsidence monitoring stations with the simulated subsidence value of model constrainted by the PS-InSAR monitoring subsidence deformation field,the fitting degree of them is higher.This provides a certain reference significance for coupling of the space monitoring technology and numerical simulation technology to establish a relatively more realistic subsidence model.