Comparative Laboratory Evaluation of Resin-Grouted Roof Bolt Elements

摘要

In laboratory testing, the Bureau of Mines established criteria by which common resin-grouted roof bolting systems can be evaluated and compared. Ultimate strength and stiffness were determined for nontensioned full-column, point-anchor, tensioned full-column, and debondable resin-grouted bolts, and for variations on full-column bolts. Bolt performances were compared using the performance of the 3/4-in full-column resin-grouted bolt as the standard. New and innovative systems can also be qualitatively compared against this standard. Various host mediums were used in the testing: sandstone, concrete, simulated coal, simulated shale, and plaster. Bolt performances expected in other mediums can be inferred from the response patterns obtained in these mediums.