京津高铁沿线地面沉降特征(北京段)

Characteristics of land subsidence along Beijing-Tianjin inter-city railway(Beijing section)

针对京津高铁(北京段)存在的地面沉降问题,采用时序合成孔径雷达干涉技术获取研究区2010—2015年间地面沉降信息,结合地下水实测数据,采用交叉小波的方法探讨不同层位地下水位变化与地面沉降的关系,最后结合研究区内可压缩黏土层分布情况分析地面沉降与可压缩黏土层厚度的关系。结果表明:研究区年均沉降速率最大值为121 mm/a;地面沉降滞后承压水位变化9～10个月,滞后潜水位变化4个月;位于同个冲洪积扇控制范围的地面沉降速率随可压缩黏土层厚度的增加而增大。本研究对于科学有效防控不均匀地面沉降对线状地物的损害具有实用意义。

In this paper,according to the land subsidence problem existing in the Beijing-Tianjin inter-city railway(Beijing section),time-series synthetic aperture Radar interferometry was used to obtain the land subsidence information from 2010 to 2015.Combined with the measured data of groundwater,the relationship between the groundwater level changes and the land subsidence at different layers was studied by using the cross wavelet method.Finally,the relationship between land subsidence and compressible clay thickness was analyzed based on the distribution of compressible clay in the study area.The result showed that average annual maximum sedimentation rate in the study area was 121mm/a,that the ground subsidence lagged the pressure level of the pressure level by 9~10 months,with the lag time of the submersible being 4 months,and that the ground subsidence rate in the control range of the same flushing fan increased with the thickness of compressible clay layer.This research is of great significance for the scientific effective prevention and control of uneven ground settlement on linear ground objects.