Abstract: With the special geological and hydrological conditions of Sanshandao gold mine，there were large amounts of bittern ions in backfill mixing water according to the test results，which has an adverse effect in slurry gravity transportation.The possibility of using superplasticizer to improve slurry transportation properties was explored in this paper to realize high concentration gravity transportation.The backfill slurry was prepared with using classified tailings，backfill water，cement and adding different kinds and amounts of superplasticizer.The slurry settling and bleeding rates were tested by standing in the measuring cylinder.And the rheological properties were tested by using R/S-SST rheometer.The influence law of superplasticizer on slurry settling and rheological properties were revealed by comparative analysis.The results showed：The slurry mixed with 0.5‰ naphthalene superplasticizer suffered the largest decline in bleeding rates.And it provided an effective way of reducing stope dewatering pressure；The slurries with 0.5‰ naphthalene superplasticizer admixture under high cement-tailings ratio condition and 0.5‰ polycarboxylene superplasticizer admixture under low cement-tailings ratio condition suffered the largest decline in settling rates；The rheological property of backfill slurry contained bittern can be represented as Bingham flow pattern.The best transport efficiency could be achieved by mixing 0.5‰ polycarboxylene superplasticizer when the slurry viscosity and yield stress both showed relatively low values.In conclusion，the suspension of backfill slurry contained bittern could be enhanced by superplasticizer.And the slurry viscosity and yield stress were both effectively reduced.Thus the pipe wall abrasion was decreased.

Key words: Cemented backfill, Superplasticizer, Backfill slurry contained bittern, Rheological properties, Settling properties