Rock anchor

Claim 1

A rock anchor assembly comprising: a metallic tubular element adapted to be inserted into a bore hole so that one end portion thereof extends a distance from the closed end of the bore hole and the other end portion thereof extends from the opening of said bore hole, said other end portion thereof containing a threaded section for receiving a clamp nut; an anchor plate having a size larger than the bore hole and abutting against the face of said bore hole between the clamp nut and said face; at least one reinforcing element disposed in said tubular element, said reinforcing element comprising a resin bonded glass fiber member; filling means for introducing a curable plastic material into the bore hole, said plastic material holding the reinforcing element in position within said tubular element; at least one sealing ring disposed around the external surface of the tubular element adjacent said threaded section for sealing the bore hole wall when the head of the rock anchor is introduced into the bore hole; said tubular element extending a short distance from the open end of the bore hole and the reinforcing member extending beyond said tubular element into close proximity to the end of said bore hole; said external surface of the metallic tubular member being indented in certain locations to increase the static friction between said metallic tubular member and said plastic material filled therein; and a sheath surrounding the tubular element and a portion of the reinforcing element, said sheath being positioned within the borehole.

Claim 14

A method of installing a rock anchor to a wall, said rock anchor including a metallic tubular element provided with a threaded portion at one end, at least one reinforcing element disposed therein, said reinforcing element comprising a resin bonded glass fiber member, an anchor plate and a clamp nut, comprising: making a bore hole in the wall; introducing the metallic tubular element containing the reinforcing element into said bore hole so that the threaded portion extends out of the bore hole, said reinforcing element including a tube containing air-relief slots adjacent the end portion which extends into the bore hole; introducing a hardenable plastic material under pressure into the bore hole, the air inside said bore hole being permitted to escape through said air-relief slots, said plastic material penetrating through the length of the tubular element until if flows out the open end thereof; permitting the plastic material to harden; and placing the anchor under tensile stress by pressing the anchor plate against the face of the bore hole by screwing the clamp nut on the tubular member against the anchor plate.

Claim 15

A method of installing a rock anchor to a wall, said rock anchor including a metallic tubular element provided with a threaded portion at one end, at least one reinforcing element disposed therein, said reinforcing element comprising a resin bonded glass fiber member, an anchor plate and a clamp nut, comprising: making a bore hole in the wall; introducing the metallic tubular element containing the reinforcing element into said bore hole so that the threaded portion extends out of the bore hole, said reinforcing element including a tube containing air-relief slots adjacent the end portion which extends into the bore hole; introducing a hardenable plastic material under pressure into the bore hole, the air inside said bore hole being permitted to escape through said air-relief slots, said plastic material penetrating through the length of the tubular element until if flows out the open end thereof; permitting the plastic material to harden; and placing the anchor under tensile stress by pressing the anchor plate against the face of the bore hole by screwing the clamp nut on the tubular member against the anchor plate.