顶管施工对既有地铁结构变形和内力的影响分析

Analysis of the Influence of Pipe Jacking Construction on Deformation and Internal Force of Existing Subway Structure

为预测天津地区某雨污水管道顶管施工对既有地铁结构的影响,基于MIDAS GTS/NX平台建立了三维地层-结构-顶管施工数值模型,模拟分析了新建管道顶管施工全过程中既有地铁区间盾构隧道、轨道的力学响应。结果表明:顶管工作坑围护结构施工与开挖、雨水管道顶进对既有结构的影响较明显,污水管顶进施工造成的影响较弱,故需重点控制顶管工作坑开挖及大直径管道的顶进施工。顶管施工全过程中,既有结构变形均在控制值范围内。

In order to predict the influence of rainwater-sewerage pipelines jacking construction on the existing subway in Tianjin area,a 3D numerical model of stratum-existing structure-pipe jacking construction was estab⁃lished based on MIDAS GTS/NX platform.In this paper,the mechanical responses of shield tunnel and track in existing subway section during the whole process of pipe jacking construction of new pipeline are simulated and analyzed.The results showed that the construction and excavation of pipe jacking pit and the jacking of rainwater pipeline have obvious influence on the existing structures,while the jacking of sewerage pipeline has weak influence,therefore,this project needs to focus on controlling the excavation of pipe jacking work pit and the jacking construction of large diameter pipeline.The deformations of the existing structure are within the control values range during the whole process of pipe jacking construction.