Shallow City Tunnel Construction Law Of Ground Settlement

In urban tunnel project,the tunnel construction will inevitably cause the ground subsidence and stratum displacement,the ground subsidence caused by the tunnel construction is often strictly restricted because of the surrounding buildings and numerous underground pipelines,therefore,the study and forecast of the ground subsidence rules seems to be very important. The settlement of ground surface due to the construction of tunnel is the main cause which results in the damage of the appearance and the function of buildings on the ground surface. In general, the buildings on ground surface are not considered in the design of a subway tunnel, and the main measurement for protecting buildings is to control the settlement of ground surface in the construction process. The practical method in construction is to set a upper limit of settlement for controlling the construction or modifying the primary design. This method ignores the specific types of buildings on the ground surface and the interaction between buildings on the ground surface and a tunnel, so those strengthening measures are not very reliable.This paper 3D fast Lagrangian analysis software FLAC3D pairs Shallow city tunnel construction process caused Surface subsidence regularity study research different factors for tunnel construction provide theoretically guidance.First introduced the main shallow tunnel construction method and tunnel construction method of the applicable conditions and the advantages and disadvantages, and briefly introduces the construction technology of mining method. And then briefly introduced the three-dimensional fast Lagrangian FLAC3D and numerical simulation software, the theory and application of analysis software FLAC3D established numerical model of shallow tunnels, the last of different factors on settlement of shallow tunnels and surface characteristics influence, focus on the surrounding properties, methods of excavation and support of the tunnel on the North Water Transfer, excavation diameter and formation conditions of the impact on the surrounding rock.