Open Cut » Rock Mechanics
This research project has been undertaken with the aim of improving knowledge in the behavior of the rock slopes at Australian coal mines. A large database of Slope Stability Radar (SSR) deformation data has been searched and analyzed for rock failures using parameters related to deformation and velocity.
A total of 762 deformation data folders were reviewed which included 73 mine wall collapses. For each collapse, parameters associated to deformation and velocity of movement, at various stages of the collapse, were determined and then analyzed in order to find common behaviors. Several attempts to find correlations between the different variables at collapse and prior collapse didn't lead to very reliable mathematical expressions that could be universally applied in the coal industry, however, the information compiled provide guidance on how to proceed in similar circumstances.
The project serves as a reliable starting point to guide existing or new users of SSR systems, or any other geotechnical instrumentation, to detect deformation patterns and understand trends in the potential for mine wall collapses.
In order to provide a framework for readers of this document, the report comprises review of existing literature on rock wall deformation, velocities, and collapse prediction. This framework also serves as the basis of the analysis undertaken on the data.
With the aim of providing further validation to the coal data analysis, the authors describe their thoughts and considerations based on their global experience in monitoring deformations and collapses in all types of mines. For future research, it is recommended that this study would be better framed and understood when considered alongside research in other types of minerals and mining practices.
The experience of the authors, supported by the collapse data summarized within the report, lead to recommendations on the use of the monitoring systems and for best practice setting of alarming parameters. Based on the findings of this report, the main recommendation for any mining operation interested in utilizing monitoring systems to provide early warning on precursor deformations of collapse, is to understand and value the importance of human interaction with the system, and appreciate geotechnical judgment that must be applied before making decisions based data.
Finally, the authors propose future research considerations to continue this project for coal mines, and for any other type of ore in the mining industry.