selbstschneidende and selbstschneidende and selbstbohrende gebirgsanker

摘要

PCT No. PCT/AU91/00503 Sec. 371 Date Jun. 8, 1993 Sec. 102(e) Date Jun. 8, 1993 PCT Filed Oct. 29, 1991 PCT Pub. No. WO92/08040 PCT Pub. Date May 14, 1992.A self-tapping rock bolt having a discontinuous threaded profile with a plurality of cutting edges and at least one flute extending along the length of the rock bolt. The cutting edges are adapted to cut a threaded profile in the internal surface of a pilot hole so that the threaded profile of the rock bolt interlocks therewith. An internal axial hole is provided to enable water to be injected through the rock bolt as the threaded profile is being cut. The discontinuous threaded profile is tapered to form a lead-in section such that the height of the leading edge of each segment of the discontinuous threaded profile progressively increases from a leading end of the rock bolt.