Mining Engineering > GATE 2022 > Rock Mechanics
The modified Lauffer diagram as shown in the figure relates to roof span, RMR and stand-up time. In a metal mine, roof span of a drive is 4 m. If the RMR of the rock mass changes from 40 to 60, then the stand-up time increases by a factor of __________.(round off to two decimal places)


Correct : 50.00
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