Effects of Superplasticizer on the Hydration, Consistency, and Strength Development of Cemented Paste Backfill

Minerals

Abbas Taheri¹  Bo Ke²  Hongwei Deng³  Junren Deng³  Jian Zhang³ 

[1] School of Civil, Environmental and Mining Engineering, The University of Adelaide, Adelaide 5005, Australia;School of Resource and Environment Engineering, Wuhan University of Technology, Wuhan 430070, China;School of Resources and Safety Engineering, Central South University, Changsha 410083, China;

关键词: cemented paste backfill;    superplasticizer;    full tailings;    hydration;    nuclear magnetic resonance;    fluidity;    strength;   

DOI  :  10.3390/min8090381

来源: DOAJ

【 摘 要 】

The strength and consistency of cemented paste backfill (CPB) are of key concerns in the stope stability and cost control for underground mines. It is common practice to use additives, such as superplasticizer, to improve the performance of CPB. This study mainly focuses on the effects of superplasticizer on the hydration, consistency, and strength of CPB. In this study, a polynaphtalene sulfonate was used as the superplasticizer. The binder is a mix of 33.3% ordinary Portland cement and 66.7% fly ash. The CPB specimens with a tailings-binder ratio of 3:1 and a solid concentration of 70% were then tested by a low field nuclear magnetic resonance system after different hydration times. Effects of polynaphtalene sulfonate on the hydration, fluidity, and strength were investigated. Results showed that the polynaphtalene sulfonate has a strong influence on short-duration hydration, which may contribute to the strength increase of CPB. It has been demonstrated that the polynaphtalene sulfonate improved the fluidity of the CPB mixture. With the increased dosage of polynaphtalene sulfonate, the slump increased. It was also found that the polynaphtalene sulfonate dosage has a negligible effect on the 1 day (d) strength while it has a strengthening effect on the 7 d, 14 d, and 28 d strength of CPB specimens.

【 授权许可】

Unknown