抄録
In this study, numerical simulations on the boulder breakage by the hydraulic breaker were carried out by using Distinct Elements Method (DEM). The boulder consisted of 4106 elements and two kinds of chisels were used in this simulation. One is a flat type chisel and the other is a wedge type chisel. These chisels were penetrated into the boulder and the generation and development of the fractures in the boulder were simulated. It was confirmed through this simulation that the flat type chisel broke the chisel largely although the large impact force and hitting number are necessary. On the other hand, the wedge type chisel needed small impacting force, and hitting number to break the boulder was also small.
