Authors: Fourie, AB


Cite As:
Fourie, AB 2016, 'Relying on suction to maintain slope stability', in PM Dight (ed.), APSSIM 2016: Proceedings of the First Asia Pacific Slope Stability in Mining Conference, Australian Centre for Geomechanics, Perth, pp. 3-11,

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The stability of open pit slopes in saprolitic materials may be enhanced by ensuring the slopes remain as dry as possible. This is because, when the saprolite remains dry or relatively dry, negative pore water pressures, also known as suctions, may contribute significantly to the stability of these slopes. Simple actions to retain the slopes as dry as possible, particularly in zones of the slopes where critical shear zones develop are described. Additional complications are due to the existence of cemented bonds in undisturbed saprolites. These bonds are remnant from the original, parent bedrock and may provide a very brittle response when subjected to loading. The need to separate the contribution of these various factors to the shear strength of saprolites is essential to correctly quantifying the stability of slopes in saprolitic materials.

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