Rapid Measurement and Estimation of Saturated Hydraulic Conductivity of Mineral Slurries

Abstract

Large strain consolidation (LSC) behaviour of mineral slurries regulates the performance of tailings management and reclamation plans. The hydraulic conductivity-void ratio relationship primarily influences this behaviour, dominating the long-term performance of fine-grained slurries with higher initial water contents. However, the determination of this function can be very challenging and time-consuming, considering the long duration of the conventional tests and significant variation in hydraulic conductivity values with the wide range of void ratios.This study focuses on identifying or creating a rapid method to evaluate the large strain consolidation parameters, especially the k-e relationship, of fine-grained soils by (i) establishing a relationship between the consolidation parameters and more easily measured properties and (ii) designing a self-weight consolidation setup to evaluate the k-e relationship using Instantaneous Profiling Method (IPM). For part (i), a total of 79 k-e data sets of fine-grained soils are examined. Using some of the above innovations, equations are found that require only a single measurement of hydraulic conductivity at a single void ratio. When applying these new equations to the k-e data set, 94% of the predicted k values are within an order of magnitude of the measured data points. This is likely sufficient for this method to be used as a screening tool for tailings treatments. For part ii), the design of a prototype consolidometer is introduced, and the consolidation behaviours of various finegrained soils are evaluated. The prototype is designed as an alternative experimental setup to conventional laboratory tests and aims to rapidly assess the k-e equation for fine-grained soils. The test column was instrumented with tensiometers and capacitance-based sensors c 