| Urban infrastructure has developed rapidly,the international metropolis has become increasingly formed,the subway project has been in the national first-tier cities to build.However,the impact of the construction disturbance on the stratigraphic environment is becoming more and more prominent.The construction of the subway tunnel has a potential threat to the urban construction environment.Urban subway tunnels along the direction of the city's main road,will inevitably cross a large number of underground pipelines.Subway construction will lead to additional stress and deformation of underground pipelines,thus affecting the safety of underground pipelines.In order to ensure that the subway construction can be used in the normal use of the pipeline under the premise of safe and orderly,which requires scholars to further study the subway construction on the impact of the pipeline changes in the law.In this paper,the underground pipeline of Qingyue Intercity Tunnel of Xi'an Metro Line5 is used as the engineering background,and the typical sewage pipeline is selected as the object of study.The monitoring data are analyzed and the numerical simulation method is used.The influence of the step method on the formation and the pipeline is analyzed in detail.The influence of subway construction on adjacent pipelines is systematically studied.In the process of analysis and research,the following conclusions are obtained:1?When the face of the tunnel is covered with the ground surface,the influence of the surface subsidence caused by the interaction between the ground fissure and the tunnel face is mainly in the deformation area where the ground fissure activity is strong,and the variation trend of the surface subsidence as a whole shows a step change.2?In the construction of the step method,the settlement of the underground pipeline in a step construction is more prominent,reaching 44.3% of the total settlement,28.7% of thetwo steps,19.9% of the three steps.Therefore,in the construction process,pay attention to the construction of a step control,can achieve the role of reducing the settlement of the pipeline.3?The construction of the step,the tunnel construction caused by the formation of settlement changes is the largest formation subsidence occurred in the vault range,the maximum lateral convergence occurred in the arch waist position.4?The influence of the construction of new tunnels on the existing structures in the loess area is in the range of 0 ~ 3.2D(D is the outer diameter of the tunnel),and the maximum settlement rate is near 1.0D.Therefore,when the new tunnel intersects the important underground pipeline By increasing the spacing between the two to eliminate the impact of construction. |
PDF Full Text Request