Study On Lining Structure Analysis And Staged Construction Simulation Of Large-Section River-crossing Shield Tunnel

Nowadays in the respect of large shield tunneling across river or sea, new demands are put forward on existing testing means and methods on the one hand, traditional design and construction methods can not meet the requirements on great depth and large section on the other hand. Relaying on the Shanghai Yangtze River tunneling with the largest external diameter (15 meter), which is used as road and rail, reasonable design method of tunnel lining and effective staged construction simulation means of construction are deeply researched. The impact of grouting load and segment joint on the lining's stress behavior is analyzed. The interaction regularity of large section close space shield tunnel across river is researched with this subject, and some useful conclusions are presented.This paper concludes several aspects as follows:1,The applicability for large section river-crossing shield tunnel of several calculation models is researched and the influence of complex stratum is analyzed. Preliminary discussion is given to lining optimization.2,The mechanics analytic model of segment joint is presented according to its feature. The rotational stiffness is calculated in different combined action of axial force and moment.3,The relationship between transverse effective ratio and longitudinal equivalent rigidity is researched by considering transverse effective ratio with modified routine method.4,The construction process is divided into several parts and the process of large section close space river-crossing shield tunnel is simulated by staged construction finite element method to get the interaction regularity.Reasonable calculation model and effective staged construction simulation means of large section river-crossing shield tunnel are of great significance to improving design level, reducing cost, controlling safety and so on.