Wide span underground chamber excavation and primary supportin intensely weathered rocks;

Influence of construction machinery eccentric load on stability of trench excavation;

Application of the NATM construction in the Beidoupo tunnel excavation and support;

When road route passes low-lying or pond,it is often needed to dig or fill in silt.

4 tunnel in the 51st bidding section of Xihan Superhighway, and in the light of the features of the tunnel under the weak geological condition, this paper puts forward corresponding pre-controlled construction scheme, which includes the excavating and supporting, monitoring and measuring, and the construction of big arch springing and temporary inverted arch, etc.

Combining Guangzhou s east section Longtoushan tunnel construction of Jingzhu main national line,it put emphasis on introducing double side drift method by tunnel excavating and its advance supporting and initial supporting can provide the reference to similar engineering construction.