Stability Analysis On Deep Foundation Pit Support Of Hefei Qinghe Station Rail Transit Line5

Today,the subway has become a symbol of urban economic prosperity and development of transport,but also one of the important means of transportation in modern cities.Metro not only integrates into people's daily life,but also plays an indispensable role in urban planning and social environment.Hefei began to carry out subway construction in2009,turning a new page in the construction of underground engineering in Hefei.On the planning of the MTR,by 2025,Hefei planned 12 tracks and opened and operated.In the construction of the main structure of the subway,the safety of the structure is the primary problem of the project,and the excavation of the foundation pit is the core part of the whole project,the normal excavation of the foundation pit is an important prerequisite to ensure the safety of the foundation pit,but also the foundation of the subway station.After nearly a decade of development,Hefei's underground transportation project has developed rapidly.With the smooth opening of Line 1 and Line 2,and the construction of Lines 3,4 and 5 in full swing,the deep foundation pit engineering technology has become more and more mature.In the process of foundation pit excavation,because of the limited space in the city,the supporting engineering plays an important role in the process of foundation pit excavation.It not only provides working space for the excavation of foundation pit and the construction of main body,but also plays a protective role in the foundation pit project,and controls the potential adverse factors around the foundation pit in a controllable range.Inside.This paper takes the deep foundation pit project of No.5Qinghe Road Station of Hefei Urban Rail Transit as the background,and simulates the excavation and support process of the main structure in the actual project by using the finite element software,discusses the influence analysis of the retaining structure in the deep foundation pit on the excavation and the stability of the foundation pit,and makes use of the stability theory of the deep foundation pit.On the estimation method,the stability of the deep foundation pit of Hefei Metro Line 5 is simulated by Midas GTS finite element software.The following key problems are analyzed.Summarizing the current study situation of stability theory and numerical methods of the development of deep foundation home and abroad.Analyze the changes of deformation and strain during the excavation and enclosure of deep foundation pit theoretically.Using Midas GTS software to analyze the concrete working condition during differentconstruction steps,observing the rules of foundation's deformation and strain under different working conditions by extracting results.The accurate numerical simulation is the prerequisite of the study of stability.Sorting out the results of numerical simulation,modeling the type of 1 and 2support and observing the deformation to judge the practicability of other types.Analyze other possible factors on deep foundation pit enclosure stability.As for the models built for numerical simulation,the magnitude of deformation and displacement should contrast to the requirement of the surrounding environment's protection.