Abstract: In order to explore the impact of freeze-thaw cycles on the strength of the consolidated tailings， freeze-thaw cycles， uniaxial compression and scanning electron microscopy （SEM） were used to study the consolidated tailings at different freezing temperatures. The variation of consolidation strength under different curing ages and freezing temperatures was studied， and the evolution rules of hydration products and microstructure characteristics within consolidation mass under different freezing and thawing cycles and freezing temperatures were analyzed. The results showed that the strength of consolidation increases first and then decreases with the increase of freezing-thawing times at the same freezing temperature and different curing ages， which basically follows the quantitative relationship of quadratic power function. At the same curing age， the strength of the consolidated mass is decreased with the decrease of freezing temperature. With the increase of freeze-thaw cycles， the internal structure of the consolidated mass shows as sparse， dense and loose under the same curing age and freezing temperature. Under the same curing age and freeze-thaw cycles， the lower the freezing temperature is， the less the amount of hydration products such as C-S-H gel and crystal ettringite （AFt） are produced， and the sparser and looser the internal structure of the consolidated mass displays.

Key words: Tailings consolidation and discharge, Freeze-thaw cycles, Uniaxial compression, SEM