Evolution Characteristics of Uneven Land Subsidence Along Beijing-Tianjin Inter-City Railway

Beijing-Tianjin inter-city railway travels through the edge of land subsidence funnels. With the increase of uneven settlement, it becomes a threaten for the safe operation of the railway. Time series interferometry technology is used to obtain the surface deformation along the railway, and cross-section method is used to reveal the spatial distribution and evolution characteristics of uneven subsidence. The results show that the gradient can well reflect the regional uneven land subsidence, which has presented positive correlation with the thickness of compressible layers, groundwater pumping and the railway operation. Compression layers are the basic preconditions, while the groundwater exploitation and utilization and the railway operation are the main reasons for land subsidence. The spatial-temporal distribution of the two factors may jointly determine the evolution of the non-uniform land subsidence.