Development of the hydraulic rock splitting system using hydraulic pressure

The objective of this study was to develop potentially suitable hydraulic rock splitting system using hydraulic pressure for rock excavation. Used method of the hydraulic rock splitting system was applying hydraulic pressure in the interval area of the double packer. Many tests of hydraulic rock splitting were conducted using double packer at the free surface in the biotite granite area. The rock excavation from a host rock by the hydraulic rock splitting technique, which is not represented by the direction of the maximum horizontal principal stress, is adjusted by the rock fragment divided by a vertical hydraulic fractures with direction parallel to the borehole axis and a horizontal hydraulic fractures with rotational direction perpendicular to the borehole axis. The location of the slot was a depth of 60-90cm of direction parallel to the borehole axis. Used hydraulic pressure and flow rate values were 23 MPa, 26LPM, respectively. As results, hydraulic fractures occurred in the free surface of the biotite granite area. The induced hydraulic fractures by the splitting was extended 200cm across borehole and the induced splitting of the depth of 180 cm was occurred at the both side of the borehole. These results confirm the viability of the hydraulic rock splitting system for rock excavation.