Toh, JCW, Green, DKE, Swarbrick, GE, Fowler, MJ & Estrada, BE 2013, 'Earthquake stability assessment for open pit mine slopes', in PM Dight (ed.), Proceedings of the 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering
, Australian Centre for Geomechanics, Perth, pp. 1187-1201, https://doi.org/10.36487/ACG_rep/1308_84_Toh
Earthquake stability assessment of large open pit mine slopes brings together two areas of slope engineering that are usually quite separate. To account for the scale and nature of open pit slopes, analysis techniques widely used for small scale civil infrastructure slopes need to be adapted and then extended.
The first part of this paper presents a framework for earthquake stability assessment of open pit mine slopes that has been used in practice by the authors. The framework attempts to provide consistency across various analysis techniques, from pseudo-static analysis to dynamic numerical modelling. Guidance is given for selecting an appropriate earthquake load coefficient for pseudo-static analysis.
The second part of this paper presents two examples of dynamic numerical modelling. One example demonstrates that the earthquake response of large rock slopes is highly dependent on the interaction between the seismic hazard, the resonant behaviour of the slope and surrounding ground, the rock mass character, and the slope geometry, and it follows that understanding dynamic site response is an integral part of earthquake engineering for large rock slopes. The other example presents parts of a detailed analysis of slope stability and deformation, and compares the results to those obtained from simpler analysis methods.
Ambraseys, N.N. and Menu, J.M. (1988) Earthquake-induced ground displacements, Earthquake Engineering and Structural Dynamics, International Association for Earthquake Engineering, Vol. 16(7), pp. 985–1006.
Ashford, S.A., Sitar, N., Lysmer, J. and Deng, N. (1997) Topographic effects on the seismic response of steep slopes, Bulletin of the Seismological Society of America, Vol. 87(3), pp. 701–709.
Bouchon, M. (1973) Effects of topography on surface motion, Bulletin of the Seismological Society of America, Vol. 63(2), pp. 615−632.
Geo-Slope (2007) Geostudio 2007 Quake/W software,
Itasca (2007) FLAC software v6,
Makdisi, F.I. and Seed, H.B. (1978) Simplified procedure for estimating dam and embankment earthquake-induced deformations, ASCE Journal of the Geotechnical Engineering Division, Vol. 104(GT7), pp. 849–867.
Read, J. and Stacey, P. (2009) Guidelines for open pit slope design, CSIRO Publishing, Victoria, Australia.
Simulia (2012) Abaqus software v6.12,
Standards New Zealand (2004) NZS1170.5, Structural design actions, Part 5: Earthquake actions – New Zealand.
Toh, J.C.W. (2010) Seismic analysis for open pit mines, Australian Geomechanics Society, Sydney Chapter Symposium, 13 October 2010, Sydney, Australia.