| In order to further guide the design and development of splitters and guide the engineering practice, in the article a computerized numerical simulating analysis method is used to restudy the rock fracturing mechanism caused by the rock drill-splitter. Lucubrate and analyze the influence of mechanical parameter and engineering parameter change to rock splitting effect. It is very important in theory and practical engineering to development of splitters and improve the rock breaking effect by splitters.In the research, in order to simulate and analyze the rock splitting mechanism, C9N radial splitter (Produced by Germany DADAR Company) and a prototype of axial- radial splitter(Produced by Laval University in Canada) is used as the research objects. Contraposing the shortage of rock splitting theory of splitters, finite element analysis software ANSYS9.0 is applied and 3D contact models of splitter feather and rock are set up to study stress distribution nearby the hole, the influence of mechanical parameter and engineering parameter change to rock splitting effect with elasticity mechanics and fracture mechanics theory. The main research achievements and conclusions are as follows.Set up 3D contact models of splitter feather and rock. have solved the load problems of the force when the press distribution exerted by splitter on the hole walls is unknown under the function of splitter in the simulaition, and obtain the press distribution on the hole walls.Analyze the distribution of the stress nearby holes along radial, shear and axial directions caused by the radial splitter and axial- radial splitter. When breaking rocks by radial splitter, the maximum stress is not lied on the orifice but on the hole wall atθ=0°andθ=180°, 137mm depth and stress concentration factor(SCF) is 1.14; When by axial- radial splitter, the maximum stress is on the bottom of the hole and the stress ratio (σmax/qN)of the maximum stress(σmax) and the spress constant (qN) value is 0.9.Simulate and study the rock splitting mechanism of radial splitter and axial- radial splitter under several free surfaces and also study the splitting effect of two splitters work together. According to the result analys, as the free surfaces adding the maximun stress in the rock mass has a tendency to increase and the position of the maximun value appears on the hole wall in the direction of free surface. Under the work of two splitters, stress superimposition appear obviously on the linked-center line of the two holes, and the value is bigger than two times of the stress value which produced by one splitter on the same point.Simulate and study the rock-breaking mechanism of axial-radial splitter, build multi-group computation models, lucubrate and analyze the influence of wedge angle and hole depth change to rock-breaking effect of axial-radial splitter. According to the result analys, radial stress(σr) and shear sress(σθ) minishes as wedge angle(α) increases, axial stress(σz) increases as wedge angle(α) increases. When the ratio of splitting depth and hole's diameter(h/d) is 4, the rock-breaking efficiency of axial-radial splitter is highest.
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