Grout plug for rock bolts

Claim 1

IN COMBINATION WITH A GROUTABLE ROCK BOLT ASSEMBLY WHICH INCLUDES A TENSION ROD HAVING A THREADED OUTER END, AN EXPANSION UNIT SECURED TO AN INNER PORTION OF SAID ROD, A BEARING PLATE ENGAGING THE OUTER PORTION OF SAID ROD AND NORMALLY DISPOSED AGAINST THE SURFACE OF A ROCK FORMATION, NUT MEANS ENGAGING THE THREADED OUTER END OF SAID ROD, AND A TUBE DISPOSED BESIDE SAID ROD AND TRAVERSING SAID BEARING PLATE, A SEAL FOR CLOSING A BORE IN A ROCK FORMATION RECEIVING SAID ROD AND EXPANSION UNIT, COMPRISING: A RESILIENTLY DEFORMABLE SLEEVE HAVING A TAPERED PERIPHERAL SURFACE AND NORMALLY SURROUNDING SAID ROD WITH THE LARGER END OF SAID SLEEVE FACING OUTWARD, AND SAID RESILIENT SLEEVE HAVING A CENTRAL RECESS EXTENDING FROM THE SAID LARGER END FOR A FRACTIONAL PART OF THE AXIAL LENGTH OF SAID SLEEVE; A CORE SLEEVE OF REINFORCING MATERIAL HAVING A PERIPHERAL SURFACE ENGAGING SAID RECESS, AND HAVING A SUBSTANTIALLY AXIAL DISCONTINUITY FOR RECEIVING SAID TUBE, SAID CORE AND DEFORMABLE SLEEVE HAVING AXIALLY-ABUTTING SURFACES AT THE INNER PORTION OF SID DEFORMABLE SLEEVE TO TRANSFER AXIAL FORCES FROM THE OUTER END OF SAID CORE SLEEVE TO THE INNER PORTION OF SAID DEFORMABLE SLEELVE.