Study On Ground Subsidence Regularity Caused By Subway Construction Under The Typical Geological Conditions

With the development of urban construction and the accelerating of transportation facilities, subway has become the mainstream direction of urban public transport facilities construction with its quick, safe, intelligent etc features in recent years. With large-scale construction of urban subway, at one time many geotechnical problems will also come forth. Most of the urban subway construction located in the downtown area where have intensive buildings, dense underground pipelines and busy Traffic. In the subway tunnel excavation process, however, it will bring influence on ambience inevitably, and especially stratum settlement is very distinct. So, the study on Surface settlement regularity caused by tunnel construction is necessary. In this paper, the subway tunnel excavation-induced ground surface settlement is studied by using Peck formula on background of the interval line of Guangzhou metro tunnel engineering. Main content as follows:Firstly, for lateral surface subsidence data caused by subway construction in typical geological conditions, using linear regression analysis for curve fitting to measurement data, and to get general rule of lateral surface subsidence. Simultaneously according to exploration and design material, adopt Peck formula to forecast the suiface settlement caused by subway construction.Secondly, based on the statistical analysis of measured data, introduce two correction parameters to correct original Peck formula, get the suggestion value range of correction parameter for Peck formula:the maximum surface subsidence corrected paramererαis between 0.5～1.0, and the width of settlement trough corrected parameterβis between 0.4～0.9. And using the Peck formula after revised in metro construction example.Thirdly, analyzing the measurement data of longitudinal surface subsidence caused by subway construction in typical geological conditions, get the general rule of longitudinal surface subsidence.Finally, on the analysis of the basis of surface subsidence, put forward the corresponding specific control measures which should consider for different construction methods proposed in Guangzhou typical geological conditions under tunnel construction. Provide reference for the design and construction in such geological conditions of similar projects.