Abstract:

"Top heading + bench" method, which is capable of ensuring safe and rapid tunnel construction in gypsum breccia ground, is adopted for Taihangshan tunnel after analysis on different construction methods. Rapid tunnel construction is achieved by taking various measures, such as optimizing the implementation of the construction process, analyzing and determining proper bench length, optimum excavation advance rate and reasonable distance between different construction processes and implementing parallel working, partitioned borehole drilling and partitioned charging. The paper can be served as reference for the rapid construction of large crosssection tunnels in soft ground in the future.

Key words: gypsum breccia, large cross section tunnel, construction process optimization, rapid construction