A friction bolt assembly (10A,10B) which includes: an expansible sleeve having a tubular body of a steel material longitudinally extending between a leading end and a trailing end, which body has a longitudinally extending formation about which the body resiliently radially compresses or outwardly deforms and which formation extends along at least part of the body, ending at the body leading end; a rod which longitudinally extends through the sleeve body and between a first end and a second end and on which a projecting part is defined between the trailing end of the sleeve body and the second end; an expansion element mounted on or integrally formed with the rod at or towards the first end; a first load bearing formation mounted on the projecting part of the rod and which is moveable along the projecting part to abut the trailing end of the sleeve; a load applicator means mounted on the projecting part of the rod between the first load bearing formation and the second end; a rock face engaging washer mounted over the projecting part of the rod between the first load bearing formation and the load applicator means; wherein the load applicator means is actuatable on contact with the rock face engaging washer, when the rock face engaging washer is in bearing engagement with a rock face to be supported and when the first load bearing formation is in bearing engagement with the trailing end of the sleeve body, to draw on the rod to pull the expansion element into and through the sleeve body from the trailing end to cause the tubular body to radially outwardly deform about the longitudinally extending formation and wherein the sleeve is prevented from giving way longitudinally relatively to the rod under the force of the expansion element by the load bearing formation. an expansible sleeve having a tubular body of a steel material longitudinally extending between a leading end and a trailing end, which body has a longitudinally extending formation about which the body resiliently radially compresses or outwardly deforms and which formation extends along at least part of the body, ending at the body leading end; a rod which longitudinally extends through the sleeve body and between a first end and a second end and on which a projecting part is defined between the trailing end of the sleeve body and the second end; an expansion element mounted on or integrally formed with the rod at or towards the first end; a first load bearing formation mounted on the projecting part of the rod and which is moveable along the projecting part to abut the trailing end of the sleeve; a load applicator means mounted on the projecting part of the rod between the first load bearing formation and the second end; a rock face engaging washer mounted over the projecting part of the rod between the first load bearing formation and the load applicator means; wherein the load applicator means is actuatable on contact with the rock face engaging washer, when the rock face engaging washer is in bearing engagement with a rock face to be supported and when the first load bearing formation is in bearing engagement with the trailing end of the sleeve body, to draw on the rod to pull the expansion element into and through the sleeve body from the trailing end to cause the tubular body to radially outwardly deform about the longitudinally extending formation and wherein the sleeve is prevented from giving way longitudinally relatively to the rod under the force of the expansion element by the load bearing formation.