抄録
An experimental program of disc cutting was carried out using a circular rock cutting testing rig for seven selected rocks occurring in Japan, Korea and China. The program aimed at establishing the optimal condition of disc cutting, finding the relation between the peak tool force and the mean tool force, and estimating the effect of radius of cutting track on the lateral component of the tool force. The main results obtained from the present study are as follows:
(1) The optimal ratio of tool space to disc penetration that enables us to minimize the specific energy for excavating rock depends on the fracture toughness and the uniaxial compressive strength of rock.
(2) The specific energy at the optimal cutting condition correlates linearly with the uniaxial compressive strength of rock.
(3) All the components of tool force vary around their mean values, resulting in stochastic process. The lateral force fluctuates more heavily than the rolling force, although their mean values each are comparable to the other.
(4) The peak tool force is in proportion to the mean tool force: the magnification of peak to mean is 1.33, 1.60, and 1.63 for the thrust, the rolling force, and the lateral force respectively, regardless of different types of rocks.
(5) The magnitude of lateral force does not depend on the radius of cutting track when rock between neighboring tracks are cut off completely. Lateral force is always directed toward the adjacent cutting track.
