Developing and using empirical models for geotechnical design in underground coal mining

This paper addresses several historical and contemporary issues that relate to the various modelling and analysis techniques utilised in the Australian underground coal industry to assist in geotechnical design and in particular ground support design, while focussing on the development and use of empirical techniques, which have substantially contributed to improving safety and productivity both in Australia and overseas. In the field of mining geotechnics, the potential experience base is huge. For example many longwall panels are mined each year, and each one is a full-scale test of a pillar design and the ground support system(s) employed. The basic approach taken to develop empirical design tools utilising such information is described with examples including Analysis of Longwall Tailgate Serviceability (ALTS), Analysis and Design of Rib Support (ADRS) and Analysis and Design of Faceroad Roof Support (ADFRS). This paper demonstrates that empirical techniques (based on a sound mechanistic understanding of the geotechnical environment) are particularly relevant and beneficial in dealing with the complexities of geotechnical design associated with underground coal mining resulting in far superior design tools as compared to that offered by numerical or purely analytical techniques.