Abstract:

Fullface construction is conducted for Dabieshan tunnel, which is a large crosssection tunnel on WuhanHefei passengerdedicated railway. TSP advance geology forecasting is conducted during the construction of the tunnel penetrating through the fractured surrounding rock mass, so as to determine the distance and strike of the fractured zone. On basis of the geological conditions exposed by the tunnel excavation, numerical simulation and theoretical analysis are performed by means of universal distinct element code （UDEC） for the tunnel excavation and reinforcement in the fractured zone. The measured results indicate that the crown settlement pattern obtained through calculations by means of  UDEC coincides well with that obtained through insitu measurement and that the deformation values are lower than the designed allowable values, whichdemonstrates that thesurrounding rock mass and reinforcement structure of the tunnel are stable.

Key words: DEM, large cross sectiontunnel, fractured zone, construction scheme, passenger dedicated railway