... of our research project is to construct a new realistic numerical model of continuous percussive drilling, which is based on the previous Okubo-Nishimatsu's model. In this study, the parts of the previous model involved in stress wave propagation and attenuation were modified. The two models were...

... indenters. The formulas obtained can serve for general use in various kinds of rock with different diameters of the three indenter types. This analysis provides a great deal of information for practical use, such as full face boring and percussive drilling. RESUME: A travers une analyse de similitude...

...). Recently, a microcomputer simulation method of stress wave energy transfer to rock in the percussive drilling was proposed by B.Lundberg (1982–1986). In his program, however, the local contact deformation on the impact surfaces is not taken into account. But this local deformation does exist in any case...

... ABSTRACT: The drilling speed of a percussive drill may be predicted from a drillability laboratory test as a function of the drill percussion power, the hole diameter and the bit cutting edge length. RESUME: La vitesse reelle de forage d'un marteau peut être determinee à partir de test de...