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Since the reform and opening up, China’s sustained and rapid economic growth, urbanization construction, the utilization of underground space and development has been the development of. Our country always persist in taking economic construction as the center, and constantly accelerate a city to change pace. However, land natural resources is very limited, city to change the pace of construction are firmly restrained. The modern city to city periphery, area, suburban expansion but slowed down. So now the city construction focus on inner city construction, city construction appeared in high-rise buildings and subway tunnel, road has been the three-dimensional development, is a new force suddenly rises. The subway tunnel, deep foundation pit engineering application scope is very wide, has reached unprecedented level. Deep foundation pit:excavation and retaining structure design is affected by many factors, and the engineering geological condition, site conditions, construction management, monitoring and surrounding buildings are closely related. In the numerous retaining means, pile anchor retaining structure with its unique advantages in foundation pit support engineering has been widely applied in。This article take ShenYang international financial center deep foundation pit project as the background, on the pile-anchor retaining structure in deep foundation pit of in-situ monitoring test, based on the field monitoring data collation, analysis of the pile anchor supporting structure deformation, the horizontal displacement of supporting structure of pile, soil and pile settlement different offset; and on this basis, using MIDAS GTS software in numerical simulation of foundation pit supporting structure stress state and deformation was simulated, obtained in excavation of a foundation pit horizontal displacement of supporting structure of foundation pit, settlement and lateral displacement of ground surface settlement deformation law of foundation pit, at the same time through the north and south sides section excavation simulation contrast, analysis of different anchor cable on the retaining structure deformation. The main results are as follows:Summary of the deep pit deformation and pile anchor support in the domestic and foreign research present situation, the analysis method is discussed, it is pointed out that the problems to be investigated.Through the analysis of engineering example of foundation pit excavation data show that, before the stage, initial soil stress distribution; foundation pit excavation depth, with the increase of soil unloading, in effect, support on both sides of the pile under different soil pressure of retaining structure and lead to produce horizontal displacement of foundation pit, which led to the top of the settlement; the horizontal displacement of supporting structure of foundation pit is a dynamic change, with the excavation process, influence range of about2-3times the depth of excavation, in the excavation is completed, the horizontal displacement curve of a " bow " form, in a period of time and tends to be stable.Combined with practical engineering, anchor cable, considering pile soil contact role between the relationship, combined with the theory of finite element, finite element software MIDAS-GTS established with anchor cable drilling cast-in-place pile supporting structure finite element model, simulation of ShenYang international financial center deep foundation pit engineering of pile anchor retaining structure of foundation pit under the deformation, numerical the simulation results and measured data, the results are consistent convergence. Multiple fulcrum pile-anchor retaining structure of pile body maximum deformation appears in the foundation pit in the upper part, is about the depth of excavation3/4. The calculated results and the measured results, calculated values are higher than the actual value, the interaction between pile and soil and other issues also need further study, can draw can meet the need of engineering calculation method.
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