The influence of lead length on the fractures associated with leading corners and sidings

Abstract

Stopes on three reef horizons and at various depths were examined in the vicinity of inter-panel leads. The general geometry of fractures in the vicinity of inter-panels leads is outlined. The extend of fracturing parallel to the siding between leading and lagging panels was found generally to extend further into the lagging panel with increasing lead length. Curves fitted to the data seem to be asymptotic to a limiting fracture extent of about 15 to 20 m. More information is needed on the siding-parallel fracture extent associated with very long lead lengths. Other aspects requiring further investigation are outlined.