Torque transmission through rock bolts
Bragg, G. H. (George H.)
Miscellaneous PaperAbstract: A laboratory testing program was undertaken to determine the effectiveness of a 1000-ft-lb impact wrench in transmitting torque to the anchor shells of various lengths of rock bolts. The investigation was limited to testing of one impact wrench on 2-, 4-, 6-, 8-, 10-, 12-, 16-, and 24-ft-length rock bolts. Results of torque tests indicated that transmitted torque generally decreases with increasing bolt length. It was recommended that impact wrenches to be used for torquing rock bolts be proof tested in the laboratory and in the field before acceptance.
Soils and Pavements Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Impact; Rock bolts; Torque
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