Abstract: The anchor bolt assembly is of the type used in mine roofs and the like in which the anchor bolt assembly is positioned in a bore hole of a rock formation. The bolt assembly includes an elongated bolt shaft with a head on one end and is threaded on the other end and has a mechanical expansion anchor on the threaded end. A quick-setting resin cartridge is positioned in the bore hole above the threaded end of the bolt shaft and the bolt assembly is secured to the rock formation by both the expansion anchor and the resin. The anchor assembly includes a helical coil surrounding the bolt shaft for mixing the resin and urging it upwardly toward the threaded end while the bolt shaft is rotated in one continuous direction to secure the mechanical anchor to the rock formation. A method of anchoring such a bolt assembly is also disclosed.