| The problem of predicting the settlement behavior of a slurry, including mine tailing and dredging spoil, placed in an impoundment is a complex issue when geometry, production schedule, and material characteristics are taken into consideration. Currently, Gibson's one-dimensional, non-linear finite-strain model is most commonly used to describe the consolidation process and implemented in computationally efficient numerical codes. However, the translation of these one-dimensional results to the three-dimensional impoundment geometry is not always a straightforward procedure. Common approaches could possibly lead to significant over- or under-estimation of the impoundment capacity. It is proposed to develop and implement a comprehensive three-dimensional model to address these shortcomings. The model will rationally describe an upper and lower bound solution of the slurry impoundment problem. It will provide information on the slurry surface height vs. time relationships, density and permeability profiles, and mass and water balance. Thus, all necessary data will be obtained for a rational design during filling operations and for predicting post-production settlements. The modeling scheme will take the three-dimensional and implements Gibson's non-linear consolidation model with user defined production schedules. Different drainage conditions at the bottom boundary will be properly modeled to determine the time-height relationship of the slurry surface at any point in the impoundment. With easy manipulation of these properties, multiple production schedules, impoundment geometries, and depositional variations can be examined with relative ease. |
