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It is nearly two decades since a formal terminology and a classification scheme were proposed for rock reinforcement hardware and applications. That combined framework was used to clearly identify concepts associated with reinforcement mechanics in a manner that was consistent and robust enough to characterise all reinforcement systems. Since that time, many new reinforcement systems have been developed and it can be shown that they all fit within the proposed classification scheme. Most recently, a complementary new terminology and a classification scheme for surface support, also based on mechanics, have been developed. This framework is invaluable in the design of ground support schemes, the planning of testing and instrumentation programs and the development of software used to simulate the static and dynamic response of rock reinforcement and support systems. It will be shown that the terminology and classification schemes are valid today and will so remain into the future because of the laws of mechanics.

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This paper presents the results of a comprehensive monitoring program designed to investigate the extent of blast induced damage experienced by rock masses extracted by bench stoping methods. An array of triaxial geophones and extensometers were used to monitor blast vibration attenuation and measure hangingwall deformations during stope extraction. In addition, pre and post surveys of the hangingwall rock mass were conducted using a TV borehole camera and cavity survey instrumentation. These surveys were later used to calibrate damage profiles into the stope hangingwalls.Peak particle velocity, hangingwall deformation measurements and stope surveys were used to develop a site specific damage model that allowed engineers to asses drilling and blasting configurations to minimise the extent of pre-conditioning and damage. In addition the study included the analysis of the frequency response, displacements and accelerations experienced by the excavation as extraction and mine filling progressed. This work aimed at improving our understanding of the influence of blasting on the dynamic behaviour of stope hangingwalls.The study demonstrated that estimates of the maximum extent of rock mass pre-conditioning and/or damage made through the application of the Holmberg-Persson approach compared well with measured results. In addition, the study found that dynamic loading imparted on an exposed hangingwall from subsequent stope blasting was also expected to contribute to rock mass weakening and that mine filling was crucial to arrest further deterioration. Hangingwall accelerations were used to demonstrate that larger openings may be more susceptible to dynamic loading.

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