A rock bolt (1) has a tubular body (2) with first and second ends (3, 4). The first end (3) is substantially sealed. A threaded rod (5) extends from the tubular body second end (4) for receiving a nut 102. A portion (6) of the tubular body (2) at the second end (4) is crimped on to the threaded rod (5). A rock bolt assembly is also disclosed comprising a rock bolt (1), a sleeve (105) coaxially mounted oil the rock bolt (1), a resin cartridge (104) received in the sleeve (105) and a collar (107) mounted on the leading end (106) of the sleeve (105) to engage a rock face and prevent the sleeve (105) from entering a hole in the rock face into which the rock bolt (1) is installed.