Interaction characteristics of geosynthetics with fine tailings in pullout test

Abstract

New mining technologies not only exploit lower-grade ores but also produce a much higher volume of tailings as mining waste. The disposal of these tailings is a challenge for mine operators. A tailings dam is usually constructed to store these wastes safely. The dam continuously increases its height and changes geometry with the disposal of tailings, which is different from conventional dams. Therefore the stability of tailings dams is a challenge. Geosynthetics have been widely used as reinforcement in retaining walls and embankments, but their applicability to the construction of tailings dams has not previously been studied. Their applicability depends largely on the interaction between geosynthetics and fine tailings. In this paper, the interaction of geosynthetics (geobelt and geogrid) with fine copper ore tailings is studied through laboratory pullout tests. The test results reveal that the interaction characteristics are influenced by tailings particle size, density, moisture content, and vertical load. It is found that the maximum friction coefficient between geosynthetics and the fine tailings is less than 0.22, which is lower than the published data for natural soils.