地铁隧道下穿既有铁路基础变形控制标准研究

地铁隧道下穿既有铁路施工时,线路基础变形会引起轨道几何尺寸发生变化,从而影响运营安全。首先,基于地铁隧道下穿既有有砟轨道线路路基的工程实际,建立有限元模型对地铁隧道下穿既有铁路变形规律进行分析。然后,以既有线路的轨道高低容许偏差管理值为依据,制定不同速度等级、不同埋深条件下铁路基础变形的控制标准和下穿施工时的沉降速率控制标准,为类似工程沉降控制标准的制定和施工安全管理提供参考。

Study on control standard of foundation deformation of subway tunnel of ballasted track

When the subway tunnel passes through the existing railway construction,the deformation of the line foundation will cause the change of the track geometry,thus affecting the operation safety.Firstly,based on the engineering practice of subway tunnel passing through the existing track of ballast subgrade,a fi nite element model is established to analyze the construction foundation and line deformation patterns of subway tunnel passing through.Secondly,based on the allowable deviation management value of the existing track,the control standard of foundation deformation and settlement rate in control standard of underpass construction under different speed levels and buried depth conditions are formulated,so as to provide reference for the establishment of settlement control standard and construction safety management of similar projects.