Several studies have been conducted in the last decade to understand the geotechnical properties (e.g., strength, stress-strain behaviour of mine tailings backfill. However, most of these studies were conducted on cemented tailings backfill (i.e., mine backfill containing cement as binder) and at temperatures above zero. However, the progressive depletion of ore available at shallow depths in a number of underground mines in Canada means that underground mining operations are increasingly being carried out not only at greater depth but also in permafrost regions, i.e. at subzero temperatures. There is a lack of information about the geotechnical properties of mine tailings backfill at subzero temperature conditions. Furthermore, many mines located in Permafrost regions are very far from the urban places where the cement is produced. This makes the use of cement in mine backfill in permafrost very expensive due to the high transport cost of the cement. To tackle this issue, there is a relative new trend to use the technology of frozen tailings backfill (FTB). The FTB is a mixture of tailings sprayed with ice cold water. FTB specimens with total water content of 6%-45%, static compaction pressure of 25 kPa, and length to diameter ratio of 2:1 are tested. Results of uniaxial compressive strength tests with constant loading rate of 2.54×10~(-2)mm/s are analyzed and interpreted. An optimum total water content of 25%-35% is found with which the strength and the Young's modulus of the FTB are 1.4-3.2MPa and 35-58MPa, respectively.
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