Investigating energy dissipation and deformation capacity of ground support schemes under dynamic loading: results from LaRonde and Kittilä mines’ drop test program

Authors: Durham, C; Falmagne, V; Caron, M-E; Pyy, A; Brändle, R Download Paper Open access courtesy of:

DOI https://doi.org/10.36487/ACG_repo/2465_35

Cite As:
Durham, C, Falmagne, V, Caron, M-E, Pyy, A & Brändle, R 2024, 'Investigating energy dissipation and deformation capacity of ground support schemes under dynamic loading: results from LaRonde and Kittilä mines’ drop test program', in P Andrieux & D Cumming-Potvin (eds), Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 589-606, https://doi.org/10.36487/ACG_repo/2465_35



Abstract:
Over the past decade, mining-induced seismicity and the consequences of dynamic loading on ground support schemes have become a focus of ground control management and one of the major challenges at LaRonde mine, as it extends below 3,000 m. The Kittilä mine manages high deformation in some areas and is experiencing dynamic conditions at depth. In some rare occurrences, dynamic loading from seismic events have exceeded the capacity of ground support schemes at both sites. Furthermore, the ground control practices implemented to safely manage seismic conditions in development drives have been largely successful, but introduce operational efficiency and cost challenges. Thus as the mines progress deeper there is a need to implement ground support schemes that are not only tougher but also more efficient to install, considering current practices and available equipment at each operation. In line with a process of continuous improvement, a dynamic drop testing program was initiated at Geobrugg’s facility in Walenstadt, Switzerland, in collaboration with Geobrugg, LaRonde and Kittilä mines, to study the performance of various ground support schemes for both sites. This paper details the experimental program and the results of tests with a comparative analysis of the tested schemes. This large-scale laboratory testing program and the detailed analysis process of the conducted drop tests enable better understanding of the dynamic behaviour of different configurations of ground support schemes using the products currently employed at both mines, and help to identify possible avenues for improving the ground support scheme. The testing program is intended to guide improvements in the design of ground support schemes for deep mining conditions.

Keywords: deep mining, seismicity, dynamic ground support schemes, dynamic testing, rockburst, high stress

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