The influence of desiccation and unsaturated soil mechanics on geotechnical performance of tailings storage facilities

Tailings are the waste product of mining process, which normally consist of soil particles, water and chemical components. Conventional slurry deposition of tailings consists of hydraulic deposition of high water content slurry tailings behind a dam. This type of deposition might not be safe due to considerable risk of dam failure associated with susceptibility to static and dynamic liquefaction. Dewatered tailings were proposed to reduce the risk of dam failure by increasing the strength of tailings and potentially removing the cost of dam construction. Water recycling is another motivation of dewatered tailings. Since the dewatered tailings are normally deposited sub-aerially in tailings storage facilities, the volume change, hydraulic conductivity and shear strength behaviour of the deposited tailings are a function of unsaturated soil properties and fall in the realm of unsaturated soil mechanics. It is found that there is a stress history in cyclic deposition of dewatered tailings, which can be simulated by unsaturated soil mechanism and measuring soil-water characteristics curve of tailing.

Keywords:

Tailings , Unsaturated Soils , Geo-environmental Engineering , Tailings Dam SWCC ,