Research On The Influence Of Subway Construction On The Displacement Of Adjacent Underground Pipelines

With the development of metro construction,urban underground space has been continuously developed and utilized,and the conflict between new metro projects and underground pipelines becomes more and more obvious.The excavation of metro project has changed the soil environment around the pipeline,resulting in the displacement of adjacent pipelines.Once the displacement is too large,the pipeline will be damaged.This will not only affect the construction progress of the metro project,but also affect the daily life of the surrounding citizens and even the safety of their lives and property.The consequences are difficult to estimate.Therefore,It is necessary to study the influence of subway construction on the displacement of adjacent underground pipelines,and then put forward the corresponding prevention and control.Based on the influence of actual metor construction on adjacent pipelines,this paper first analyzes the influence and cause of excessive pipelines displacement and damage,and analyzes the displacement of pipelines from the deformation mechanism of pipelines,and summarizes the factors affecting pipelines displacement.Based on the actuality of the subway project,the numerical analysis model of the foundation pit-pipelines and the numerical analysis model of the interval tunnel-pipelines are established respectively to analyze the displacement law of the adjacent pipelines in the metor construction.The numerical simulation is used to study the displacement law of the pipelines under the influence of internal factors.The sensitivity of each intrinsic factors to the displacement of the pipelines.Then the displacement of the pipelines under the actual metor construction is monitored,and the measured results are compared with the simulated calculations to verify the feasibility of the model and the law of pipelines displacement.Finally,according to the pipelines displacement law and the sensitivity of each factor,the displacement of the pipelines is given measures and recommendations.Through the above research,when the underground pipelines is parallel to the foundation pit of the station,the displacement of the pipelines changes regularly with the change of intrinsic factors.The order of sensitivity of the intrinsic factors is space,depth,diameter and material.The key monitoring and prevention positions are the pipeline position corresponding to the pit angle of the foundation pit to 0.167L(L is the length of the foundation pit).When the underground pipeline is orthogonal to the tunnel,the displacement of the pipeline varies regularly with the intrinsic factors.The order of sensitivity of the intrinsic factors is pipe diameter,buried depth and material.The key monitoring and prevention locations are in the range of two-dimensional(D is tunnel diameter)around the orthogonal axis of the pipeline and the tunnel.The study provides a theoretical reference for the normal use of adjacent underground pipelines in the construction process of metro projects,and is of great significance.