盾构隧道下穿高速铁路路基沉降控制标准研究

Subgrade Settlement Control Standards for Shield Tunnel Crossing underneath High-speed Railway

为了合理制定隧道下穿高速铁路的变形控制标准,采用现场调研和统计分析等方法,对高速铁路轨道、扣件及路基的相互作用关系开展研究,提出高速铁路路基沉降控制标准的制定方法。研究结果表明:1)轨道最大可允许变形由下穿点轨道扣件的最大可调整量、当前已用调整量和当前平顺度等数据确定;2)轨道变形控制标准根据下穿点周边环境及列车实际运行速度选取合适的安全系数,在最大可允许变形量的基础上进行折减;3)路基变形控制标准根据路基与轨道变形的相互关系确定。提出的轨道变形控制标准适用于高速铁路无砟轨道,路基变形控制标准适用于土质地层盾构隧道引起的路基变形。

The deformation control standards for tunnel crossing underneath high-speed railway is of great significance.As a result,the interaction among high-speed railway tracks,fasteners and subgrade is studied by field investigation and statistical analysis,and the formulation method of subgrade settlement control standards for high-speed railway is proposed.The study results show that:(1)The maximum allowable deformation of the track is determined by the maximum adjustable amount of the track fastener,the current adjustment amount and the current smoothness,etc.(2)An appropriate safety factor for the control standards of track deformation should be selected according to the surrounding environment and the actual running speed of the train,reducing on the basis of the maximum allowable deformation.(3)The deformation control standard of subgrade shall be determined according to the correlation between subgrade and track deformation.The deformation control standards for the track is applicable to the ballastless track of high-speed railway,and the deformation control standard of the subgrade is applicable to the subgrade deformation caused by shield tunneling in soil stratum.