CLASSIFICATION AND RESEARCH METHODS OF ROCKBURST EXPERIMENTAL FRAGMENTS
HE Manchao1，2，YANG Guoxing2，3，MIAO Jinli1，2，JIA Xuena1，2，JIANG Tingting2
(1. State Key Laboratory for Geomechanics and Deep Underground Engineering，China University of Mining and Technology，Beijing 100083，China；2. School of Mechanics and Architecture Engineering，China University of Mining and Technology，Beijing 100083，China；3. The Engineering Design Research Institute of Equipment of PLA，Beijing 100028，China)
Abstract：A serial of rockburst samples are tested under rockburst simulating system of China University of Mining and Technology，Beijing. Different methods may be used to obtain information of fragments，including scanning medium fragments with area about 100 mm2 by SEM(scanning electronic microscope) and the large fragments by 3D laser scan technology and measuring fragments size. The measuring parameters include mass，length，width and thickness. In order to analyze fragments of different scales conveniently，fragments are divided into four classes including coarse，medium，fine and micro grains and corresponding research methods are defined. The calculated process and results of fractal dimensions with different methods are introduced with an instance of rockburst granite sample. The linear correlation is obvious when fractal dimensions are calculated by methods of double divided interval for measuring data，image process of binary and small island for 3D laser scan data calculation. The fractal dimensions are different when using different methods. Based on the fractal dimensions of different groups of fragments，the degree of crushing of every group of fragments can be analyzed and base data may be provided to further investigate characteristics of energy changing during rockburst.
