Methodology and computer program for applying improved, inelastic ERR for the design of mine layouts on planar reefs.

Abstract

Use of the mine layout design criteria of ERR (Energy Release Rate), APS (Average Pillar Stress) and ESS (Excess Shear Stress) have not provided a good control of seismicity. It has become apparent that more complex models of rock mass behaviour are needed. Furthermore, such models should be integrated with observed seismicity of recent mining to enable us to better estimate future expected seismicity within a rock mass of uncertain geological structures, strength and virgin stress conditions. This project follows from GAP612c “The Relationship between ERR and seismic energy release for different geotechnical areas”. It considers concepts of a limit to the load-bearing capabilities of the unmined ground, stress drop during seismic events and the visco-plastic models of Napier and Malan (1997) and Malan (2002). Methodologies and a computer program (MINF) are developed during this project that write synthetic catalogues of seismic events to simulate the rock response to mining