Study On Influence Of Shield Construction On Existing Bridge Pile Foundation And Control Measures

At present,shielded tunnels are widely used in assembled lining structures,and this technology is rarely used in tunnels built by the mining method.At present,domestic construct railway tunnels by the mining method.The widespread use of prefabricated components not only improves the overall quality of construction,but also has significant effects in shortening the construction period and saving costs.The research on the mechanical properties of fabricated linings is further strengthened,not only because it can cooperate well with the mining method construction,but also more importantly,it will be widely used in the construction of railway tunnels in the future.This paper refers to the common models used in the design and calculation of tunnels at home and abroad,and uses the finite element method to carry out numerical simulations.The mechanical characteristics of fabricated linings in railway tunnels of mining methods are studied.The main research contents are as follows:(1)With reference to the experience and research results of shield tunnels and railway tunnels at home and abroad,the mechanical calculation model of the tunnel assembled lining structure is analyzed,and the "load-structure method" calculation model suitable for this paper is determined.(2)In accordance with the principle of component division based on the “comprehensive consideration of structural forces,component fabrication and installation,etc.”,a plan for partitioning an inverted arch was proposed.Through the analysis of the characteristics of the inverted arch structure,a reasonable division scheme is determined.(3)Based on the rational division plan of the invert,the overall lining is divided according to the construction division principle.An alternative component division scheme is proposed,and the optimal component division scheme suitable for the fully prefabricated lining structure is determined through a comparative analysis of structural force rationality and construction feasibility.(4)The minimum thickness of the optimal partitioning scheme for fully prefabricated structures at different levels of surrounding rock was studied.The mechanical properties of different annular joint stiffnesses and segment widths were analyzed.(5)The stress characteristics of the lining structure are analyzed when considering the spatial effect of staggered seams.