Abstract:
In order to reveal the subsidence rule of shallow stratification at the depth of 102 meters in Tianzhu land subsidence monitoring station, the monitoring data of layers are analyzed.Research find that: ①Land subsidence mainly occurs in clayey soil layer vertically, the development of land subsidence is proportional to the content of clayey soil, and the stratum of clayey soil is compressed under the action of continuous increase of ground stress.②In terms of seasonal variation characteristics, there is a high correlation between the seasonal deformation characteristics of land subsidence and the dynamic change trend of groundwater level in a hydrological year.The rate of land subsidence slows down in the high water period and increases obviously in the low water period.③The changes of soil deformation at different depths and its proportion in the total settlement are closely related to the corresponding variation range of aquifer water level.The compression of shallow soil in Beijing ground subsidence area slows down at present.Most of the soil in the middle and deep parts continue to compress at a faster speed.The cohesive soil with different buried depth has elastic deformation, plastic deformation and creep deformation, which has significant viscoelastoplastic.the shallow flow in Tianzhu station flows from the first silty layer to the first middle sand layer, and the middle flow flows from the second fine sand layer to the second fine sand layer.the deep water flows from the third silty clay layer to the second fine sand layer.