Analysis And Study On Retaining Structure Of Expansive Soil Deep Foundation PIT In Chengdu Metro Cuijiadian Station

With the rapid development of urban underground space development in China, the excavation retaining technology of deep foundation pit and the research on the qualitative of expansive soil have made a certain achievement, but with the complexity of the deep foundation pit retaining technology under the environment of expansive soil, security in chengdu area subway deep foundation pit retaining structure are studied, it is necessary to analysis and research the security of deep foundation pit retaining structure of subway in Chengdu.This thesis, taking Chengdu metro Cuijiadian foundation pit as an example, on the basis of site investigation, collecting data and analysis about peculiar regional special soil clay in Chengdu area-Chengdu clay, and then through theoretical analysis, numerical simulation and dynamic monitoring, will try to look for a reasonable way for foundation pit supporting. Taking the engineering safety, construction difficulty, the economic efficiency, environmental protection and project cycle into consideration, the research provides reasonable suggestions on deep foundation pit supporting design and construction.In turn to get the general conclusion, guide the similar project construction, especially provide certain reference function in Chengdu area of deep foundation pit engineering.This article is under the premise of the actual project, choosing appropriate way of foundation pit supporting from the design theory, and through numerical simulation, the stability of the calculation of engineering, combined with the monitoring data, and then determine preferred way of foundation pit supporting under the Chengdu clay and weathered mudstone geological conditions.(1) Through the existing geological exploration report and the corresponding engineering data, analysis the engineering environment, engineering geological condition and hydrogeological condition of foundation pit, and the corresponding evaluation for site geological conditions;(2) On the basis of the existing engineering geologic condition, hydrogeological condition and the combination of theoretical analysis, choose reasonable pit supporting scheme and construction scheme;(3) Combined with the actual situation of the project, calculate the excavation of deep foundation pit construction process in numerical simulation, and analysis on the stability of retaining structure,based on the horizontal displacement of pile foundation;(4) Taking use of construction process of the informatization construction of monitoring data, analysis the displacement deformation of foundation pit retaining structure and the security of tructure, to verify the safety of the containment plan.