Bearing Capacity of Desiccated Tailings
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 125, Issue 7
Abstract
The development of matric suctions in soils contributes to their shear strength, resulting in an enhanced factor of safety against bearing-capacity failure. In this paper, matric suction profiles of desiccated mine tailings are predicted from a steady-state solution for evaporative conditions, and from an isothermal mathematical model that simulates liquid and vapor water flow through soils. The shear-strength envelope with respect to matric suction is established by testing reconstituted tailings samples in a modified triaxial cell, in which matric suction can be controlled. The contribution of matric suction to the shear strength is interpreted as an additional apparent cohesion for use in bearing-capacity calculations. Because of the nonlinearity of the shear-strength profile, a numerical method of analysis is adopted to predict the ultimate bearing capacity of the desiccated tailings. A subsequent decrease in bearing capacity following 2D water infiltration into a partially capped tailings deposit and accompanying suction loss is investigated.
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Information & Authors
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 125 • Issue 7 • July 1999
Pages: 600 - 609
History
Published online: Jul 1, 1999
Published in print: Jul 1999
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