Long Span Section Construction Technology Of Subway Tunnel

Geological conditions of interzone tunnel from west peace-bridge station to east road station of north earth town in fifths route of Beijing subway is very complex , and groundwater is rather in abundance. Interzone long span tunnel have more than 230 meter, the various types of transect reach to eleven, and transect switch would have been done every ten and twelve. Main aim of construction research is how can find out a safe and fast construction method, due to far lag of time limit for a project.By referring to large numbers of correlated technology data, and receiving guidance from many underground engineering experts, this thesis had made detailed research on construction method of long span tunnel, including the special research of transverse passage of vertical shaft switching to main tunnel, two-arch tunnel as well as switchover between long span tunnel , and brought forward reasonable optimized construction method. The technology of transverse passage of vertical shaft switching to main tunnel is key innovational technology taken up with on this thesis, which had been applied in Beijing subway tunnel construction. By draw comparision of two techonology, it make clear that the techonglogy brought forward on this thesis is feasible in practice. In the construction of the long span tunnel, this thesis brought forward the key technology of the standard section switch to long section;this technology is another innovation in construction. It had made an analyse and optimized the the design of two-arch tunnel by making use of plane FEM theory analyse, and this received good economical effect. The monitoring and controling technology reflected sufficiently the bear force state of wall rock of complex tunnel construction;this technology is a key technology which deserved put forward in the construction. In practice, this construction method was proved feasible, therefore getting safe and fast construction.