Abstract:
Incompetent rock is always related to low strengths and/orto well developed discontinuities, which are often the most essential factors leading to unstable openings. This paper outlines the deformobility and failure of incompetent rock around an opening under mining disturbances, and discribes the main requirements for opening supporting under circumstances mentioned above. Two kinds of rock-bolts with superior performances which were designed for strengtheting of incompetent masses are presented and two schemes for opening supporting combined rock bolting with reinforced shotcrete which have been used successfully in mines are given.