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The conventional disposal of slurried tailings in a tailings storage facility (TSF) leads to the formation of a beach, on which the tailings sort hydraulically, settle, consolidate, and desiccate upon exposure. Basic geotechnical testing, such as specific gravity, Atterberg limits, and particle size distribution, found that there was no particular trend of changes in the tailings properties down the beach. The settled sediment found in a settling test was slurry-like and unsuitable for conventional oedometer testing. Constant rate of loading (CRL) consolidation testing is more representative of the continuous disposal of tailings slurry than conventional step loading. Consolidation testing in a slurry consolidometer was conducted and captured from a slurry-like to soil-like state. A slow rate of loading increased the test time, while a too quick rate of loading built up very high excess PWP. The test results showed different stages of consolidation, depending on excess PWP development and dissipation, and applied stress.

Overtopping failure of reinforced tailings dam may cause significant damage to theenvironment and even loss of life. In order to investigate the feature of overtopping of the reinforcedtailings dam, which has rarely appeared in the literature, the displacement, the phreatic level and theinternal stress of dam during overtopping were measured by a series of physical model tests. Thisstudy conclusively showed that, as the number of reinforcement layers increased, the anti-erosioncapacity of tailings dam was notably improved. It could be supported by the change of the dimensionof dam breach, the reduction of stress loss rate, and the rise of phreatic level from the tests. Based onthe erosion principle, a mathematical model was proposed to predict the width of the tailings dambreach, considering the number of reinforcement layers. This research provided a framework for theexploration of the overtopping erosion of reinforced tailings dam, and all presented expressions couldbe applied to predict the development of breach during overtopping.

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