A numerical simulation method for time-dependent growth of cracks in rocks and its validation
HUANG Da1，2，LIU Fuxing1，YANG Chao3，HUANG Runqiu4
(1. Key Laboratory of New Technology for Construction of China in Mountainous Area，Ministry of Education，Chongqing University，Chongqing 400045，China；2. State Key Laboratory of Coal Mine Disaster Dynamics and Control，Chongqing 400044，China；3. Key Laboratory of Geological Hazards on Three Gorges Reservoir Area，Ministry of Education，China Three Gorges University，Yichang，Hubei 443002，China；4. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection，Chengdu University of Technology，Chengdu，Sichuan 610059，China)
Abstract：There are many micro-flaws in rock. In this paper，it is proposed that every cell in the numerical model includes a virtual micro-fissure without the thickness and with the normal distribution in dip angles and length. The growth rate and the mode of the micro-fissure are determined based on the fracture mechanics and growth mode of cracks. When the micro-fissures grow to the boundary of the cell，the cell fails. The failure cells coalesce together and form the failure surface in rock. Taking the Burgers model as an example，the numerical modelling method is incorporated into the software FLAC. It is applied to the intact rock and to the cracked rock with single or two pre-existing flaws under uniaxial and biaxial compression loads respectively. The simulated results agree well with that from laboratory tests，which validates the proposed method.
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2017, Vol. 36 
