Penetration Experiment of Rocks by means of Disc Cutter. Study on disc cutting of rock (6th Report).

In this study, in order to make the rock cutting mechanism of disc cutters clear, and to find a simple experimental method for examining cutting performance of disc cutters, penetration experiments of disc cutters were carried out with 7 kinds of rock. The main results obtained from the present study are:(1) Beforechipping, the penetrating resistance FT is proportional to penetrating depth P as:FT=KTP3/2.The coefficient KT is proportional to uniaxial compressive strength of rocks.(2) Penetrating resistance when chipping occurs depends on fracture toughness of rock.(3) Comparing with the result of the first report, it was shown that the cutting experiment of disc cutters can be replaced by penetration experiment for examining the cutting performance of disc cutters.