DISCRETE ELEMENT ANALYSIS OF FAILURE PROCESS OF HARD ROCK WITH A PRE-EXISTING CIRCULAR OPENING
ZHANG Sherong1，SUN Bo1，WANG Chao1，YAN Lei2，3
(1. State Key Laboratory of Hydraulic Engineering Simulation and Safety，Tianjin University，Tianjin 300072，China；2. School of Civil Engineering，Tsinghua University，Beijing 100084，China；3. HydroChina Kunming Engineering Corporation，Kunming，Yunnan 650051，China)
Abstract：Based on the theory of particle flow code，the failure process of tuffaceous sandstone with a pre-existing circular opening is simulated by numerical experiments under uniaxial，biaxial and triaxial compressions. And the impact of different loading modes is analyzed from the view of peak strength，microcrack and energy. The results show that the failure of rock specimen starts around the opening regardless of loading modes. The deformation of opening under uniaxial compression is different from that under biaxial and triaxial compressions. And a macro-crack is formed on the side of rock specimen under uniaxial compression. Peak strength of rock specimen under triaxial compression is larger than that of biaxial compression at the same confining pressure. And the difference of peak strength between biaxial and triaxial compressions increases with the increase of confining pressure. Crack-initiation stress decreases with the increase of confining pressure under biaxial compression，while crack-initiation stress increases with the increase of confining pressure under triaxial compression. The change process of strain energy can reflect the failure process of rock specimen. And its peak value is greatly influenced by confining pressure. The change process of dissipated energy can reflect the extent of slip and friction between microscopic particles. And its change law is related to loading modes and confining pressure.
张社荣1，孙 博1，王 超1，严 磊2，3. 含孔洞硬岩破坏过程的离散元分析[J]. 岩石力学与工程学报, 2012, 31(s2): 3855-3863.
ZHANG Sherong1，SUN Bo1，WANG Chao1，YAN Lei2，3. DISCRETE ELEMENT ANALYSIS OF FAILURE PROCESS OF HARD ROCK WITH A PRE-EXISTING CIRCULAR OPENING. , 2012, 31(s2): 3855-3863.
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2012, Vol. 31 
