Roof Bolt Anchorage Quality Indicator/tension Decay Equalizer.
NTIS: PB 84-231455 Available for Reference At Bureau Libraries :158 pages
This report presents the results of a laboratory and field research program to design and develop a torque-thrust controlled bolter with the capability to (1) predict the "quality of anchorage" attained while installing mechanical anchor roof bolts and (2) improve the uniformity and tension levels achieved among a group of roof bolts. The prediction accuracy of the anchorage quality algorithm ranged from low to moderate because of the complexity and variability of the phenomena involved. The best roof support with mechanical anchor bolts was achieved by simply installing them under proper torque-thrust control with a hardened washer under the bolthead. The results showed a threefold uniformity improvement and a 75% increase in mean tension levels over conventionally installed roof bolts.
CP; Final Contract Report;
NTIS Accession No.
NTIS: PB 84-231455. Available for Reference At Bureau Libraries
Terra Tek, Inc.