Research Of Deep Foundation Pit Supporting Technology In Qingdao Haian Road Subway Station

With the progress of the society and the rapid development of economy, the subway plays more and more important role in city. It becomes effective transportation to alleviate the traffic pressure on the city. Because the subway has a lot of advantages, such as high speed, low energy consumption, etc. Manylarge and medium-sized cities have started the construction of the subway project. But subway construction is a relatively complex process. Foundation pit excavation of subway station is the basis of the subway construction. The stand or fall of foundation pit supporting will have direct impact on the stability of foundation pit. It has great significance for the entire project.The paper takes the deep foundation pit engineering of Qingdao Haianroad subway station as the research background. The pit is located in the downtown area of the city. It has many surrounding buildings. Multiple pipelines are through its underground. Ground geomorphic type is erosion slope. According to the deep foundation pit engineering data and actual situation, we select the steel pipe piles and prestressed bolt support structure. The stability of foundation pit are calculated. It includes Anti uplift calculation, Anti-piping stability calculation, Anti-pressure head stability calculation, etc.Considering the station high mileageend with a thick backfill, because seepage effect, the soil for the stability of retaining structure significantly, the paper researches on the infiltration characteristics of the soil and the soil strength characteristics, obtained with the influence law of groundwater level change in strength.Through the field monitoring data collection, analysis, we can judge the influence of excavation on the surrounding environment and the stability of foundation pit itself.Monitoring data mainly includes the surface subsidence, deformation of retaining structure, anchor axial force change, ground water level change and the settlement of surrounding buildings, etc. According to the monitoring data reflects law to guide the construction and guarantee the construction smoothly.The paper research results for the subway deep foundation pit supporting design and construction has a certain theoretical significance and reference value.It can be used in the actual project.