Rearch On The Deformation Mechanism Of Excavation Retaining Structure And Construction Control

ABSTRACT:With the continuous development of the city, the space of city has increasingly become a factor restricting the development of city, so the development and utilization of city underground space has become an inevitable trend of modern city.At the same time the construction of city underground space makes the scale and depth of excavation increasing. So the deformation of excavation is paid more attention. The deformation of retaining structure of the excavation is an important factor affecting the deformation of excavation. There are many factors that effect the deformation of the retaining structure of the excavation. How to effectively control the excavation deformation is an important problem of excavation engineering. This thesis has simulated the specific example with finite element mehtod, and compared simulation results with the mearsured datas, then analyzed the deformation of the excavation retaining structure. The main contents of the thesis are as followes:(1) This thesis summarizes the domestic and international research status of excavation deformation, and studies the deformation mechanism of excavation from aspects of retaining structural deformation n ground settlement and basement uplift.(2)Combining with the excavation engineering of Yongtai village subway station of Beijing subway line8. this thesis uses finite element method to study the deformation of this excavation retaining structure. Then thesis analysizes some factors which effect the deformation of the excavation retaining structure.These factors content Over-excavation, Ground loading,pretension of bracing,buried depth of retaining structure,stiffness of retaining structure,stiffness of bracing.(3) From the study of the measred data, this thesis analysizes the deformation of excavation retaining structure from the view of practical engineering, compared simulation results and mearsured datas. Then thesis gives some construction measures which reduces the deformation of excavation retaining structure.