IDENTIFICATION METHOD OF COMPLEX ROCK BLOCKS USING ELEMENT RECONSTRUCTION AND AGGREGATION TECHNIQUE
ZHANG Yuting1，2，XIAO Ming2，DING Xiuli1，WU Aiqing1
(1. Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources，Yangtze River Scientific Research Institute，Wuhan，Hubei 430010，China；2. Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering，Ministry of Education，Wuhan University，Wuhan，Hubei 430072，China)
Abstract：In order to cope with the issue of block identification during the construction process of engineering rock masses containing complex excavation boundaries，a new method for identification of rock blocks is presented based on element reconstruction and aggregation technique. Firstly，the sophisticated mesh gridding technique is employed to establish meshes(e. g. finite element mesh)，thus realizing the accurate simulation of complex excavation boundaries. Then，the modeling method for geological discontinuities based on element reconstruction is employed；thus inserting the geological discontinuities which are widely distributed in rock masses into the meshes. Afterwards，the block construction method based on element aggregation technique and handling procedures for finite structural planes are presented；thus realizing the identification of complex rock blocks based on meshes finally. As the identified block system is defined on meshes，all specific information of block system can be obtained through the elements and nodes of meshes. The visualization of blocks can be also realized using mesh graphic display platform. The validation examples indicate that when the structural planes are considered either infinite or finite，the block identification and corresponding stability analysis results are identical to those derived from common software for block analysis. The presented method is further illustrated with its application to a large-scale hydropower underground cavern complex；and its effectiveness and superiority can be verified. Therefore，the presented method is determined to be a new approach for block analysis，in which complex excavation of engineering rock mass can be considered. Its implementing procedures are totally independent from the traditional topology-based block identification algorithms，thus providing a new tool for block stability analysis.
2012, Vol. 31 
