顶管下穿铁路路基设计分析

Design and Analysis of Railway Subgrade under Pipe Jacking

目前市政管线多采用顶管法穿越铁路路基的方式,在顶进过程中不可避免地会对管涵周围土体产生扰动,使铁路路基沉降变形,当变形超过一定范围时,会严重影响铁路运营安全。针对此问题,从下穿铁路路基顶管设计、线路加固、监测等技术要求方面进行全面阐述,并采用岩土工程有限元软件建立三维模型,模拟工作井钢板桩施工、基坑开挖以及管涵顶进等多种工况,并对各种工况下铁路路基的沉降变形进行全面的数值计算与分析,得出控制工况最大的沉降变形为-1.41 mm,在可控范围内。

At present,pipe jacking method is often used for municipal pipeline crossing under railway subgrade,and the process of pipe jacking will inevitably disturb the soil around the pipe culvert,resulting in settlement deformation of the railway subgrade.When the deformation exceeds a certain range,it will seriously affect the safety of railway operation.Aiming at how to safely cross the railway subgrade by pipe jacking.This paper comprehensively expounds the technical requirements of pipe jacking design,line reinforcement,monitoring,etc.of the railway subgrade under crossing,and through the use of geotechnical finite element software to establish a three-dimensional model,simulate the steel sheet pile construction of the working shaft,foundation pit excavation,pipe culvert jacking and other working conditions,comprehensively calculates and analyzes the settlement deformation of the railway subgrade,and obtains that the maximum settlement deformation under the control working condition is-1.41 mm,which is within the controllable range.It can provide reference for similar projects in the future.