Study On The Effect Of The Composite Foundation Settlement Under Foundation Pit Dewatering In West Jinan Railway Station Of Beijing-Shanghai High-speed Railway

This thesis based on the Beijing-Shanghai High Speed Railway, Established in the research topics of the key technologies of deep soft soil and soft soil sections composite foundation holded by Ministry of Railways,We set the Field monitoring test of Jinan West Railway Station Subgrade as the Project Background, and combined with the Geological survey information, to analyze the influence of the dewatering of foundation pit to the Composite foundation.The Beijing-Shanghai High Speed Railway run through the Bohai Economic Zone and the Yangtze River Delta Economic Zone of our country. Along the way through Hebei, Shandong, Anhui and Jiangsu provinces, Connect the two largest city of Beijing and Shanghai, Has important economic and political significance.This paper is based on the data of spot survey, contrast and analysis the settlement and deformation orderliness in different condations (whether affected by dewatering of the foundation pit) of the subgrade,then contrast the final measurement forecasted by hyperbolic method with the filed data, make sure the influence and the degree for the dewatering of fonudation pit to the subgrade settlement. Provide experience and advice for future similar projects.By way of contrast the vaviation trend of the settlement plank, the actual measurement data for different layers and the excess pore water pressure character through Section A with Section C, Establish the effection to subgrade surface settlement and in different depth and the excess pore water pressure features for the dewatering of foundation pit.We adopt hyperbolic method calculate the final settlement for the settlement plank and different layers whether effected by dewatering of Section C, by contrast, reached the influence degree to the subgrade surface and different depth by dewatering of foundation pit.The ground surface settlement of section C has been stabilized before influenced by dewatering. Then every points appears more settlement affected by dewatering, delayed the sedimentation trend of the subgrade surface. Though the data of different layers we can find that the settlement of every depth has reached a steady state before dewatering. By dewatering of foundation pit, the points above the drainage layer all have a considerable influence and the shorter distance with the subgrade surface the more influence.