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Abstract In high stress condition，the sharp conflict between rock mass strength and stress will lead to damage to surrounding rock. Damage is the direct embodiment of the state of surrounding rock. The acoustic detection and borehole television are used to test a whole section in Jinping II deep diversion tunnel. The acoustic test results show that the section shape of low wave velocity zone is not symmetrical；and stress distribution is not completely corresponding. The borehole television was added in each acoustic drilling，a more intuitive understanding on fracture development depth and internal actual structure features of surrounding rock is obtained. In order to describe the damage zone characteristics more accurately，FLAC3D is used to calculate the stress path of the key points in different positions and analyze the stress states of the key points. Based on the discretization by UDEC voronoi polygons，adding the joint description，the influence of joint on excavation damaged zone(EDZ) is analyzed. The simulation results show that the presence of joint changes the stress distribution after excavation and leads to the difference in damage and fracture zones. With the help of particle flow code(PFC) in advantage of describing microscopic fracture characteristics，the damage zone is simulated. It is revealed the damage localization characteristics and damage zone，fracture zone distribution characteristics have the very good consistency with actual ones.
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Received: 20 May 2013
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2013, Vol. 32 
