Abstract: In order to explore the failure mechanism of rocks under linear cutting with single cutter, a large-scale model test platform was used to carry out linear cutting tests on sandstone. This study employed the fractal geometry method to analyze the geometric characteristics of cutting products, including cutting grooves and cutting fragments, at different cutting angles and different cutting depths. The experimental results show that the cutting width has a good linear relationship with the cutting depth, and increases with the increase of the cutting depth. The cutting width corresponding to the same cutting depth is the smallest when the cutting angle is 45 degrees. The fragment-size distribution of sandstone has fractal characteristics and the fractal dimension is concentrated in the range of 1.88?2.66. The fractal dimension has a good linear relationship with cutting depth and decreases with the increase of cutting depth. The relationship between fractal dimension and cutting angle can be fitted by quadratic function, but the coefficient of quadratic term of the fitted function changes from positive value to negative value with the increase of cutting depth.

Key words: large-scale model test, linear cutting, sandstone, fractal dimension, cutting parameters, cutting groove