Mining roof bolt

A mining roof bolt for anchoring in holes in mine roofs and walls comprising

• an elongate bolt having a head and a shank, at least a portion of which is threaded,
• a generally cylindrical hollow casing made of a deformable material and surrounding the shank along a substantial portion of the length thereof,
• elastomeric particles disposed in and substantially filling the casing,
• a cap nut having a diameter greater than the diameter of said sleeve when the sleeve is not compressed, for engaging the walls of the hole into which the bolt is inserted, said cap nut, being screwable onto the threaded shank to contact one end of the sleeve,
• a holding plate disposed on the shank of the bolt between the sleeve and the bolt head so that the plane of the plate is generally perpendicular to the shank of the bolt, and
• a retainer collar disposed about the shank between the sleeve and the holding plate, and dimensioned so that it will extend at least partly into the hole when the bolt is placed in the hole to contact the other end of the sleeve.