Friction rock stabilizer and method for inserting thereof in an earth structure bore

Claim 1

A friction rock stabilizer, for insertion in a bore formed in an earth structure for stabilizing the structure comprising: a generally tubular body; said body having an elongate central axis and wall means for frictionally engaging the surface of an earth structure bore; said body further having a first, free, relaxed, transverse dimension predetermined to be larger than the transverse dimension of a bore into which it is to be inserted, and an axial length which is considerably greater than said transverse dimension; and said body also having an axially-extended slit formed through said wall means thereof to permit said body to assume a second, constrained, transverse dimension which is smaller than both said first transverse dimension and the transverse dimension of a bore into which it is to be inserted; wherein said wall means has confronting axially-extended and spaced-apart surfaces which: (1) define said slit therebetween, and (2) have key means formed adjacent to said slit-defining surfaces for: (a) receiving contraction forces thereat, and (b) responsive to such forces, for moving said slit-defining surfaces toward each other; wherein said key means comprises axially extended, substantially parallel ribs; said ribs project substantially radially, relative to said elongate axis, and extend axially along substantially the full length of said body; and at least one of said ribs projects inwardly, from said wall means, toward said axis of said body.