Escobar, AEE, Farina, P, Leoni, L, Iasio, C & Coli, N 2013, 'Innovative use of slope monitoring radar as a support to geotechnical modelling of slopes in open pit mines', in PM Dight (ed.), Slope Stability 2013: Proceedings of the 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering
, Australian Centre for Geomechanics, Perth, pp. 793-801, https://doi.org/10.36487/ACG_rep/1308_54_Farina
In the modern mining industry a comprehensive slope monitoring program, aimed at managing potential large scale instabilities and able to simultaneously detect local scale movements, should represent an integral part of every geotechnical risk assessment plan.
El Teniente provides a good example of a complex modern mining operation where stability issues have to be addressed with a slope monitoring program which is able to support geotechnical engineers not only in managing risk, but also in the interpretation of ongoing stability problems. Situated in Chile, 44 km east of Rancagua, 75 km south of the capital Santiago and at an altitude of 2,500 m, El Teniente is one of largest underground copper mines in the world and also recently integrated surface mining. The nature of the project in terms of depth, size and mining methods, and the possible interactions among the different mining processes, expose its facilities and processes to significant risk levels. Slope stability is one of the most critical sources of risk, at least in connection withsurface operations. In order to cope with these risk conditions and to possibly mitigate them, new technological solutions based on process automation and innovative concepts have been adopted. This paper describes the innovative use of slope monitoring data currently under implementation at El Teniente, which is based on the combination of radar data used in an unconventional way and other geotechnical-geological analyses. Although slope monitoring radar is a well−established safety-critical monitoring practice designed to provide alarms in case of impending pit wall slope failures occurring, there is limited published information available on the use of such a powerful technology for other purposes in mining operations such as the interpretation of slope behaviour.
This paper presents the author’s experience with using radar data to identify the most likely failure mechanisms and to assess and validate geotechnical models. More specifically, at El Teniente the proposed integrated approach involves calibrating the input parameters for finite element modelling (FEM) to replicate movements observed through the monitoring data acquired by radar. The paper presents the results of the use of radar to monitor different areas of the mine affected by stability issues, such as the Camino Principal (the main access road to the Rajo Sur pit) and the north walls of the Rajo Sur (potentially affected by slope movements) and how the data have been used to get a better preliminary understanding of ongoing instability phenomena.
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