ABSTRACT
In-situ stress is one of the important parameters in tunnel design. Nevertheless, in-situ stress measurement is not popular yet in Indonesia. The problems so far have been associated with technology availability and cost efficiency.
This research is focused to design and manufacture hydraulic fracturing apparatus, i.e. packer, hydraulic power pack and read out module at low cost. The manufacturing of packer was done as a result of collaborative work between the Laboratory of Geomechanics of the Department of Mining Engineering (DME), Institut Teknologi Bandung (ITB) and Bandung Rubber Industries (INKABA). Whereas the read out and recording module was designed and manufactured by Laboratory Control of Department of Physics Engineering, ITB. Experiments were carried out at the Laboratory of Geomechanics of DME ITB and Pongkor underground gold mine.
To date, the research has been considered successful, since the hydraulic fracturing apparatus has been performing well up to straddle packer pressure of 25 MPa. The apparatus is intentionally designed for BQ borehole and continuous improvement is on progress in order to be applied with higher capacity and the possible worst condition of borehole.
This paper therefore describes advantages and disadvantages of the hydraulic fracturing apparatus mentioned above including the use of borehole camera to support impression packer test results.
