In order to analyze the micro-stress situation and crack initiation and propagation of rock under extrusion and crushing，the numerical simulation of extrusion and crushing of particle model which is established by defining different scale characteristics of the unit body and different strength characteristics of bond between the unit bodies is conducted based on the EDEM software. The initiation and growth of multiple cracks is simulated and analyzed according to bond fracture and stress situation inside the particle model，which could reveal the microscopic mechanism of crushing of rock. At last，the influence of bite rate on the crushing of the model is analyzed，The results show that the influence of the biting velocity on the crushing of the particle model is only on the action time，but not on the fracture state and the fracture form of the model and the multi-scale cohesive particle model constructed could well reflect the characteristics of grading broken.
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2018, Vol. 37 
