method and device for breaking oberflächennaher rocks

摘要

A process for preliminary pulverizing base rock by the step of injecting high pressure water into a crack which has naturally occurred in the base rock, thereby to expand the crack. This process comprises the steps of boring a hole into the base rock by a boring rod having a plurality of boring blades mounted at the end thereof, sealing the end of the rod using gravel produced upon boring of the base rock, introducing a highly viscous fluid from the end of the rod into the sealed hole end to block the natural crack in the base rock, and finally injecting high pressure water or a high pressure and highly viscous fluid from the end of the rod to expand the crack. The base rock preliminarily pulverized can be finely pulverized with facility by means of a ripping operation. Also disclosed is an apparatus for adequately executing the preliminary pulverization of the base rock.