Beijing Subway Station Of Chaoyang Park Foundation Pit Deformation Characteristics Analysis

With the fast growing economic in our country, urbanization has accelerated markedly andinvestment in infrastructure has increased, following are the large number of ensuing municipalengineering, civil air defense projects, the city traffic engineering. Infrastructure constructionalways involves a large number of deep excavations. Usually, these excavations are locating atDowntown surrounding with high buildings and pipelines below, or in heavy traffic area. Takingthe displacement of excavation pit under control is critical to ensure the safety of theestablishment.This paper analyzed the factors affecting pit deformation to Beijing Metro Line7to the nanlou zi zhuang station project, summarizing the actual monitoring of the pile after pile surfacesubsidence and horizontal position of the data, and simulated pit excavation process by FLAC3D.This article also discussed the short side of pit coupling effecting at different stages in theexcavation pit deformation, pile insertion ratio, excavation method, the pre-stressing steelsupport on the impact of pit deformationFLAC3D numerical simulation results compared with the actual monitoring combinedshows a good match. Because the simulation does not consider precipitation, all the surfacesettlements were smaller than actual settlements while the horizontal displacements of the pilewere bigger. Excavation short side coupling effect impacts1times the short side pit width. Thecloser the short side the greater the effects. The deformation is growing fast in the lower part ofexcavation pit. In the excavation and support the implementations phase, the smaller thethickness of layered excavation, the better control of pit deformation;Pre-stress in steel support should not be too large. When increases to a certain extent, the pitdeformation control effect reduces.