Numerical Analysis Of "End-suspended Pile" Supporting System In Deep Foundation Pits For Subway Stations Constructed By Cut And Cover Reverse Method In Soil-rock Dualistic Area

Today with the rapid development of economic and fastly-changing appearanceof cities,limited surface space and traffic congestion has become the two majorproblems that hinder the development, rail transport came into being and the studiesof the subway station flourishing.In order to solve the long-term traffic effects causedby construction period on the ground,in recent years,cut and cover method was usedin downtown area of the cities in our country and over sea,such as station,LineM3,Qingdao.First,the paper analysed the applicability of the cut and cover method inspecial Soil-rock dualistic structure in Qingdao area,conclusions indicate that half-orfull-cover excavation method is more suitable to large span metro stationconstruction for a combination of soil and rock formations in Qingdaoarea.Secondly,the more economical “end-suspended pile” is widely used inexcavation in response to the feature of “soft under the hard” in Qingdao area.Thepaper relied on the engineering background of Wusiguangchang Station whichcombined the cover method and the “end-suspended pile”.Dimensional plane modelwas bulit by Plaxis finite element software.“End-suspended pile” supporting system issimulated according to the actual steps.We improved this model by analyzing themonitoring data then calculated the deformation and internal of the supportingstructure which may bear a vertical load under each condition.At last,the regularpattern varies with different factors such as width of rock shoulder and rock-socketeddepth was studied.As a result of study,the main factors were simulated in order to getthe disciplinarian of all factors,then,to make the design more eximious.