Hydromechanical Analysis of Upstream Tailings Disposal Facilities

Abstract

Very large quantities of mined ore materials are processed annually to obtain the various types of minerals that are essential to industrial processes. Due to its execution simplicity and low cost, upstream tailings disposal has been the most common method used for the surface disposal of tailings produced from processing the mined ore materials in spite of it being the most vulnerable to failure. The complex hydromechanical behavior of the upstream tailings disposal facilities (UTDFs) during their staged construction makes the traditional approaches to consolidation, stability, and seepage analyses inadequate for producing accurate and, in many situations, correct design and evaluation of these facilities. Transient coupled nonlinear finite-element analyses are carried out in this paper using the general purpose code ABAQUS to investigate the hydromechanical behavior of the UTDF during its staged construction. The analyses simulate, in combination, a number of realistic features of the UTDFs during construction, including the transient partially saturated flow within the impoundment, the two-dimensional large consolidation and nonlinear material response of the tailings, and the staged construction loading with time. The UTDF response as predicted by the numerical analyses, which are carried out in the form of comparative study on three different impoundment tailings, is qualitatively comparable with the UTDF behavior trends observed and reported in the literature.