Underground » Mining Technology and Production
Longwall geomechanical research being carried out by CSIRO's Exploration and Mining and Strata Control Technology has resulted in a better understanding of rock failure mechanisms around longwall extraction. Shear, rather than tensile failure has been the predominant failure mechanism in the Australian environments monitored. Failure has occurred further ahead of the retreating face than predicted by conventional longwall geomechanics theory. In some cases rock breakage and/or slippage has been detected several hundred metres ahead of the face position with demonstrated influences of minor geological discontinuities. Major structural features have been shown to have a dominant control on failure mechanisms. Layout geometry, the previous goafing mechanics and pore water pressure have also been shown to influence failure. Validating technologies of microseismic monitoring and new face monitoring techniques have assisted the development of predictive 2D computational modelling tools. The demonstrated 3D consequences of failure has led to the future direction of the research to further investigate these effects.
The final report includes numerous outcomes of seismic monitoring about advancing longwall faces. The results are best portrayed electronically. The final report is only available as a CD.