HYDRAULIC FOLIATING OF ORE BODIES EXPLOITED BY BLOCK OR PANEL CAVING MINING METHODS

摘要

A method of mining to increase the ore fragmentation in block caving, using the strain relief cracks surrounding the cave's back, produced during the caving progression. Intermixed (TOR) and (FF) boreholes are down drilled from top of the block up to undercut drifts. Once block undercut and ore drawn start, with each newly cave back, strain relief cracks tangential to the cave back appear, detected through breakable cables installed inside the (TOR) boreholes and connected to: a TOR (time-domain reflectometry) instrument, an oscilloscope and monitor screens. In tempo with each newly cave back. The cracked bands are hydraulically foliated through the (FF) boreholes. Foliation ascending from the undercut groove's back, in parallel layers as thin as feasible covering most of the block in height; transforming it - during the caving's upward progression - in fragile flagstones.