Coaltech Research Association

Update of Coal Pillar Data Base, Strength Formula and Probability of Failure for South African Coal Mining

Reviews how the failed and intact pillar record, tributary area loading and the safety factor concept have developed since 1960, for rock engineers and regulators.

by J N van der Merwe & M Mathey | March 2012

What this report found

Failures continued after the safety factor approach was adopted, in pillars created both before and after it, so the record of failed workings has kept growing since the original 27 cases. The database was updated and re-analysed to revise the strength formula and to set out the probability of failure associated with pillar designs.

R1500,00

Description

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