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| General method for stability evaluation of rock blocks based on numerical simulation |
| ZHANG Yuting，DING Xiuli，LU Bo |
| (Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources，Yangtze River Scientific Research Institute，Wuhan，Hubei 430010，China) |
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Abstract In order to evaluate the stability of rock blocks under various complicated conditions，a general method for stability evaluation of blocks using numerical approach was proposed based on the existed block identification method using element reconstruction and aggregation technique. The proposed method places the focus on the meshes that contain block information. Firstly，interface elements were introduced to simulate the slip and open behavior of rock block surfaces. Then，the method of determining the removability and kinematic patterns of blocks was proposed. Afterwards，the definition of the safety factor of block and its reinforcement method are proposed based on the strength reduction concept. The stability evaluation of blocks is thus realized using the numerical approach. Compared to the rigid body equilibrium method，the proposed method is able to take the influences of the initial geo-stress，rock deformation and anti-shear capacity of non-slipping interfaces into account in evaluating the block stability. Under certain conditions，the results of proposed method are equivalent to those of rigid body equilibrium. Finally，the reliability and effectiveness of the proposed method and its relationship with the rigid body equilibrium method are verified through several examples. The examples also indicate that the proposed methodology is able to reflect the influences of geometry，overburden depth and exposure height of blocks，is thus suitable for the stability evaluation of blocks during the excavation process under complicated conditions. The proposed method together with the existed block identification method form a complete system，including the identification，removability determination，kinematic pattern determination，stability evaluation and reinforcement method, which is parallel to the current methods for mechanical analysis of rock blocks (e.g. block theory).
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2017, Vol. 36 
