Reasoning of the Model Sizes in Modeling the Interaction between Tool and Rock

The article proves model sizes for modeling the interaction between tool and rock. The relevance of the research was considered. Information on the analysis of existing executive bodies (EB) used in mining, construction and municipal services is given. The finite element method is described, it was concluded in particular that the ideal model of the interaction of the executive body with the face rock would be a surface conjugated with the working of real dimensions located in an infinite massif or in a massif that is many times larger than the output. To solve the problem, cylindrical workings with a diameter D = 3.2 m were used, where the face shape is represented by two-thread helicoidal surfaces, surrounded by an around boundary massif with thickness B equal to 0.5D, D, 1.5D, 2D, 2.5D.The exterior surfaces of the model were fixed, and distributed loads corresponding to the interaction forces arising from the operation of the ETC-2086 bar unit installed on the basis of the MTZ-82 tractor were applied to the face surface. On the basis of the conducted research, the effect of the model size on the pattern of directed differentiated state (DDS) of a face was determined.