Abstract: To examine the influence of tooth shape parameters, tooth spacing, and row spacing on the rock breaking efficiency and rock damage zone under the teeth of the toothed roller cutter, different tooth shapes of the toothed cutter are selected to conduct intrusion rock breaking tests on Beishan granite with a size of 300 mm×300 mm×300 mm. The intrusion process, intrusion force, rock breaking volume, rock breaking efficiency, and characteristics of rock damage zone under the teeth are analyzed. The experimental results reveal the following: (1) The rock breaking efficiency of the selected test tooth shape with a diameter of 18 mm is the highest. (2) When the tooth spacing and row spacing ranging from 35 to 40 mm can achieve the highest rock breaking efficiency of the pick tooth intrusion. (3) The fluorescence crack visualization method is employed to analyze the distribution characteristics of rock cracks under teeth. The range of rock damage zone and crack propagation mode under different tooth shape parameters are obtained, and the crack characteristic analysis results are consistent with the results of rock breaking efficiency obtained through intrusion force and rock breaking specific energy analysis.

Key words: pick tooth, intrusion rock breaking test, tooth shape and arrangement parameters, rock breaking efficiency, damage zone characteristics