| 摘要 |
A rock bolt 10 comprising an elongate shaft 11, and an anchoring device attached to the shaft having an expansion mechanism 15 which is operable to expand radially 5 relative to the lengthwise extent of the shaft 11 to anchor the rock bolt 10 within a bore 40 drilled into a rock body 41. The anchoring device includes an annular band 45 which extends about the expansion mechanism 15 to resist expansion of the mechanism 15. The band is arranged so it can enter the bore 40 in which the bolt 10 is to be anchored in position about the expansion mechanism 15 and to maintain a 10 resistance to expansion of the expansion mechanism 15 at least until the expansion mechanism 15 has substantially fully entered the bore 40. The band 45 can be a polymeric material such as a heat shrink polymeric material in tight fitting engagement about the expansion mechanism 15 so as to conform to the external shape of the expansion mechanism 15. |
