Time variations in coal mine roof fall rates.
Cycles 1979 Jan; 23(9):197-205
Roof fall occurrence rates are examined for repetitive variations that indicate cyclic influences on coal mine roof stability. Two cyclic influences are identified, humidity and earth tides. The humidity effect on coal mine roof fall occurrence follows the annual cycle of the seasons (1 year). The tidal effect follows the synodic lunar cycle (29.53 Days).
Mining-industry; Underground-mining; Ground-control; Engineering-controls; Control-technology
OP; Journal Article