This paper was compiled to highlight the need for additional research in the area of layout design criteria
for deep gold mines. It describes aspects related to two popular design criteria used in the deep gold
mines of South Africa, namely average pillar stress (APS) and energy release rate (ERR). The early
layout designs in the gold mines were based on trial and error and most of the recommendations of
the 1924 Witwatersrand Rock Burst Committee are still valid in modern times. The introduction of APS
and ERR assisted greatly to reduce areas of high stress concentrations. Both criteria are of limited use,
however, as it is not clear what the maximum value of APS for remnants should be and ERR has a
significant drawback as no dissipative mechanisms are incorporated to allow for non-violent failure
of the rock mass. A numerical modelling study is described that illustrates the effect of total closure
on the simulated APS and ERR values of remnants. It is recommended that stress measurements be
conducted below remnant areas to better calibrate the numerical models. The need for additional rock
mass monitoring to supplement the design criteria is also discussed.
Description:
This paper was first presented
at the Deep Mining 2019
Conference, 24–25 June 2019
Misty Hills Conference Centre,
Muldersdrift, Johannesburg,
South Africa.
This work forms part of a PhD study by Yolande Jooste at the University of Pretoria.
