Case study: mining effects on convergence rates.

Geomechanical instrumentation has been used to evaluate the effects of mining on underground excavations at the waste isolation pilot plant near Carlsbad, New Mexico. The site is being developed for the disposal of transuranic nuclear wastes in bedded salt 655 m underground. During a recent mining sequence, increasing convergence rates were observed in a nearby drift ahead of the mining, separated from the mining area by a 45 m pillar. The situation was complicated by recent rib maintenance which had been performed in the nearby drift. The geomechanical data and numerical models were evaluated to determine the cause for increasing convergence rates, the effect of adjacent mining on nearby excavations and whether the minimal amount of trimming (less than 0.15 m) which occurred during rib maintenance activities affected convergence rates.
Geomechanical instrumentation has been used to evaluate the effects of mining on underground excavations at the waste isolation pilot plant near Carlsbad, New Mexico. The site is being developed for the disposal of transuranic nuclear wastes in bedded salt 655 m underground. During a recent mining sequence, increasing convergence rates were observed in a nearby drift ahead of the mining, separated from the mining area by a 45 m pillar. The situation was complicated by recent rib maintenance which had been performed in the nearby drift. The geomechanical data and numerical models were evaluated to determine the cause for increasing convergence rates, the effect of adjacent mining on nearby excavations and whether the minimal amount of trimming (less than 0.15 m) which occurred during rib maintenance activities affected convergence rates.