| a steel or fiberglass bolt inserted and anchored in a hole drilled in rock to prevent caving of the roof of a tunnel or subterranean chamber. |
rock bolt
in tunneling and underground mining, steel rod inserted in a hole drilled into the roof or walls of a rock formation to provide support to the roof or sides of the cavity. Rock bolt reinforcement can be used in any excavation geometry, is simple and quick to apply, and is relatively inexpensive. The installation can be fully mechanized. The length of the bolts and their spacing can be varied, depending on the reinforcement requirements.
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