Development and testing of a hydraulic powered diver operated rock drill and sea floor fasteners

The Civil Engineering Laboratory has developed a hand held diver operated rock drill. The drill is hydraulically powered thus eliminating the percussion and visibility problems associated with the underwater use of pneumatic rock drills. Capable of drilling holes up to 2-1/2 inches in diameter and 18 inches deep, the hydraulic rock drill has been used to install various seafloor fasteners and to provide shot holes for small explosive charges. Underwater testing of commercially available rock bolts produced data which can be used for the design of boat moorings and immobilization of undersea cables and pipelines in various types of seafloor rock. This paper discusses the development and testing of the prototype drill as well as the results of extensive testing of seafloor fasteners.